Annexe C. Historique des changements MySQL
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## Annexe C. Historique des changements MySQL

Cet appendice liste les changements de version à version dans le code source de MySQL.

Nous travaillons maintenant activement sur MySQL 4.1 et 5.0 et ne fournirons que les correctifs pour les bogues critiques de MySQL 3.23 et 4.0. Nous mettons à jour cette section lorsque nous ajoutons de nouvelles fonctionnalités pour que tout le monde puisse suivre le cours du développement.

Notre section TODO contient ce que nous planifions pour les versions 4.x. See Section B.8, « Les évolutions de MySQL (la liste des tâches) ».

Notez que nous essayons de mettre à jour le manuel en même temps que nous apportons des changements à MySQL. Si vous trouvez une version mentionnée ici que vous ne pouvez retrouver dans la page des téléchargements MySQL (http://www.mysql.com/downloads/), cela signifie que la version n'a pas encore été publiée !

La date mentionnée avec la version est la date de dernière modification dans le serveur BitKeeper, sur laquelle la version a été bâtie. Les exécutables sont généralement disponibles après quelques jours, car il faut du temps pour compiler et tester tous les paquets.

## C.1. Changements de la version 5.0.0 (Développement)

The following changelog shows what has already been done in the 5.0 tree:

- Basic support for stored procedures (SQL:2003 style). See Chapitre 19, Procédures stockées et fonctions.

- Added `SELECT INTO list_of_vars`, which can be of mixed, that is, global and local type. See Section 19.2.9.3, « Syntaxe de `SELECT ... INTO` ».

- Removed the update log. It is fully replaced by the binary log. If the MySQL server is started with `--log-update`, it will be translated to `--log-bin` (or ignored if the server is explicitly started with `--log-bin`), and a warning message will be written to the error log. Setting `SQL_LOG_UPDATE` will silently set `SQL_LOG_BIN` instead (or do nothing if the server is explicitly started with `--log-bin`).

- User variable names are now case insensitive: if you do `SET @a=10;` then `SELECT @A;` will now return `10`. Case sensitivity of a variable's value depends on the collation of the value.

For a full list of changes, please refer to the changelog sections for each individual 5.0.x release.

### C.1.1. Changements de la version 5.0.6 (pas encore publiée)

Fonctionnalités ajoutées ou modifiées :

- Updated version of `libedit` to 2.9. (Bug#2596)

Bogues corrigés :

- `MAX()` for an `INT UNSIGNED` (unsigned 4-byte integer) column could return negative values if the column contained values larger than 2^31. (Bug#9298)

- `SHOW CREATE VIEW` got confused and could not find the view if there was a temporary table with the same name as the view. (Bug#8921)

- Fixed a deadlock resulting from use of `FLUSH TABLES WITH READ LOCK` while an `INSERT DELAYED` statement is in progress. (Bug#7823)

- The optimizer was choosing suboptimal execution plans for certain outer joins where the right table of a left join (or left table of a right join) had both `ON` and `WHERE` conditions. (Bug#10162)

- `RENAME TABLE` for an `ARCHIVE` table failed if the `.arn` file was not present. (Bug#9911)

- Invoking a stored function that executed a `SHOW` statement resulted in a server crash. (Bug#8408)

- Fixed problems with static variables and do not link with `libsupc++` to allow building on FreeBSD 5.3. (Bug#9714)

- Fixed some awk script portability problems in cmd-line-utils/libedit/makelist.sh. (Bug#9954)

- Fixed a problem with mishandling of `NULL` key parts in hash indexes on `VARCHAR` columns, resulting in incorrect query results. (Bug#9489, Bug#10176)

### C.1.2. Changements de la version 5.0.5 (Bientôt publiée)

Fonctionnalités ajoutées ou modifiées :

- Added support for the `BIT` data type to the `MEMORY`, `InnoDB`, and `BDB` storage engines.

- `SHOW VARIABLES` no longer displays the deprecated `log_update` system variable. (Bug#9738)

- `--innodb-fast-shutdown` is now also settable on the fly (global variable `innodb_fast_shutdown`). It now accepts values 0, 1 and 2 (except on Netware where 2 is disabled); if set to 2, then when the MySQL server shuts down, InnoDB will just flush its logs and then shut down brutally (and quickly) as if it was a MySQL crash; no committed transaction will be lost, but a crash recovery will be done at next startup.

Bogues corrigés :

- Security fix : If mysqld was started with `--user=`non_existent_user``, it would run using the privileges of the account it was invoked from, even if that was `root`. (Bug#9833)

- Multiple-table updates could produce spurious data-truncation warnings if they used a join across columns that are indexed using a column prefix. (Bug#9103)

- Fixed a string-length comparison problem that caused mysql to fail loading dump files containing certain ‘`\`’-sequences. (Bug#9756)

- Fixed a failure to resolve a column reference properly when an outer join involving a view contained a subquery and the column was used in the subquery and the outer query. (Bug#6106, Bug#6107)

- Use of a subquery that used `WITH ROLLUP` in the `FROM` clause of the main query sometimes resulted in a `Column cannot be null` error. (Bug#9681)

- Fixed a memory leak that occurred when selecting from a view that contained a subquery. (Bug#10107)

- Fixed an optimizer bug in computing the union of two ranges for the `OR` operator. (Bug#9348)

- Fixed a segmentation fault in mysqlcheck that occurred when the last table checked in `--auto-repair` mode returned an error (such as the table being a `MERGE` table). (Bug#9492)

- Incorrect results were returned for queries of the form `SELECT ... LEFT JOIN ... WHERE EXISTS (`subquery`)`, where the subquery selected rows based on an `IS NULL` condition. (Bug#9516)

- Executing `LOCK TABLES` and then calling a stored procedure caused an error and resulting in the server thinking that no stored procedures exist. (Bug#9566)

- Selecting from a view containing a subquery caused the server to hang. (Bug#8490)

- Attempting to execute a multiple-table `UPDATE` within a stored procedure failed with a `Table '`tbl_name`' was locked with a READ lock and can't be updated` error. (Bug#9486)

- Starting mysqld with the `--skip-innodb` and `--default-storage-engine=innodb` (or `--default-table-type=innodb` caused a server crash. (Bug#9815)

- Queries containing `CURRENT_USER()` incorrectly were registered in the query cache. (Bug#9796)

- Setting the `storage_engine` system variable to `MEMORY` succeeded, but retrieving the variable resulted in a value of `HEAP` (the old name for the `MEMORY` storage engine) rather than `MEMORY`. (Bug#10039)

- mysqlshow displayed an incorrect row count for tables. (Bug#9391)

- The server died with signal 11 if a non-existent location was specified for the location of the binary log. Now the server exits after printing an appropriate error messsage. (Bug#9542)

- Fixed a problem in the client/server protocol where the server closed the connection before sending the final error message. The problem could show up as a `Lost connection to MySQL server during query` when attempting to connect to access a non-existent database. (Bug#6387, Bug#9455)

- Fixed a `readline`-related crash in mysql when the user pressed Control-R. (Bug#9568)

- For stored functions that should return a `YEAR` value, corrected a failure of the value to be in `YEAR` format. (Bug#8861)

- Fixed a server crash resulting from invocation of a stored function that returned a value having an `ENUM` or `SET` data type. (Bug#9775)

- Fixed a server crash resulting from invocation of a stored function that returned a value having a `BLOB` data type. (Bug#9102)

- Fixed a server crash resulting from invocation of a stored function that returned a value having a `BIT` data type. (Bug#7648)

- `TIMEDIFF()` with a negative time first argument and postive time second argument produced incorrect results. (Bug#8068)

- Fixed a problem with `OPTIMIZE TABLE` for `InnoDB` tables being written twice to the binary log. (Bug#9149)

- `InnoDB` : Prevent `ALTER TABLE` from changing the storage engine if there are foreign key constraints on the table. (Bug#5574, Bug#5670)

- `InnoDB` : Fixed a bug where next-key locking doesn't allow the insert which does not produce a phantom. (Bug#9354) If the range is of type `'a' <= uniquecolumn`, `InnoDB` lock only the RECORD, if the record with the column value `'a'` exists in a CLUSTERED index. This allows inserts before a range.

- `InnoDB` : When `FOREIGN_KEY_CHECKS=0`, `ALTER TABLE` and `RENAME TABLE` will ignore any type incompatibilities between referencing and referenced columns. Thus, it will be possible to convert the character sets of columns that participate in a foreign key. Be sure to convert all tables before modifying any data! (Bug#9802)

- Provide more informative error messages in clustered setting when a query is issued against a table that has been modified by another `mysqld` server. (Bug#6762)

### C.1.3. Changements de la version 5.0.4 (16 avril 2005)

Fonctionnalités ajoutées ou modifiées :

- Added `ENGINE=MyISAM` table option when creating `mysql.proc` table in mysql_create_system_tables script to make sure the table is created as a `MyISAM` table even if the default storage engine has been changed. (Bug#9496)

- `SHOW CREATE TABLE` for an `INFORMATION_SCHEMA` table no longer prints a `MAX_ROWS` value because the value has no meaning. (Bug#8941)

- Invalid `DEFAULT` values for `CREATE TABLE` now generate errors. (Bug#5902)

- Added `--show-table-type` option to mysqlshow, to display a column indicating the table type, as in `SHOW FULL TABLES`. (Bug#5036)

- The way the time zone information is stored into the binary log was changed, so that it's now possible to have a replication master and slave running with different global time zones. A drawback is that replication from 5.0.4 masters to pre-5.0.4 slaves is impossible.

- Added `--with-big-tables` compilation option to configure. (Previously it was necessary to pass `-DBIG_TABLES` to the compiler manually in order to enable large table support.) See Section 2.4.2, « Options habituelles de `configure` » for details.

- New configuration directives `!include` and `!includedir` implemented for including option files and searching directories for option files. See Section 4.3.2, « Fichier d'options `my.cnf` » for usage.

Bogues corrigés :

- The use of `XOR` together with `NOT ISNULL()` erroneously resulted in some outer joins being converted to inner joins by the optimizer. (Bug#9017)

- Fixed an optimizer problem where extraneous comparisons between `NULL` values in indexed columns were being done for operators such as `=` that are never true for `NULL`. (Bug#8877)

- Fixed the client/server protocol for prepared statements so that reconnection works properly when the connection is killed while reconnect is enabled. (Bug#8866)

- A server installed as a Windows service and started with `--shared-memory` could not be stopped. (Bug#9665)

- Fixed a server crash resulting from multiple executions of a prepared statement involving a join of an `INFORMATION_SCHEMA` table with another table. (Bug#9383)

- Fixed `utf8_spanish2_ci` and `ucs2_spanish2_ci` collations to not consider ‘`r`’ equal to ‘`rr`’. If you upgrade to this version from an earlier version, you should rebuild the indexes of affected tables. (Bug#9269)

- mysqldump dumped core when invoked with `--tmp` and `--single-transaction` options and a non-existent table name. (Bug#9175)

- Allow extra HKSCS and cp950 characters (`big5` extension characters) to be accepted in `big5` columns. (Bug#9357)

- mysql.server no longer uses non-portable alias command or LSB functions. (Bug#9852)

- Fixed a server crash resulting from `GROUP BY` on a decimal expression. (Bug#9210)

- In prepared statements, subqueries containing parameters were erroneously treated as `const` tables during preparation, resulting in a server crash. (Bug#8807)

- InnoDB : `ENUM` and `SET` columns were treated incorrectly as character strings. This bug did not manifest itself with `latin1` collations if there were less than about 100 elements in an `ENUM`, but it caused malfunction with `UTF-8`. Old tables will continue to work. In new tables, `ENUM` and `SET` will be internally stored as unsigned integers. (Bug#9526)

- InnoDB : Avoid test suite failures caused by a locking conflict between two server instances at server shutdown/startup. This conflict on advisory locks appears to be the result of a bug in the operating system; these locks should be released when the files are closed, but somehow that does not always happen immediately in Linux. (Bug#9381)

- InnoDB : True `VARCHAR` : InnoDB stored the 'position' of a row wrong in a column prefix primary key index; this could cause MySQL to complain `ERROR 1032: Can't find record …` in an update of the primary key, and also some `ORDER BY` or `DISTINCT` queries. (Bug#9314)

- InnoDB : Fix bug in MySQL/InnoDB 5.0.3 : SQL statements were not rolled back on error. (Bug#8650)

- Fixed a `Commands out of sync` error when two prepared statements for single-row result sets were open simultaneously. (Bug#8880)

- Fixed a server crash after a call to `mysql_stmt_close()` for single-row result set. (Bug#9159)

- Fixed server crashes for `CREATE TABLE ... SELECT` or `INSERT INTO ... SELECT` when selecting from multiple-table view. (Bug#8703, Bug#9398)

- `TRADITIONAL` SQL mode should prevent inserts where a column with no default value is omitted or set to a value of `DEFAULT`. Fixed cases where this restriction was not enforced. (Bug#5986)

- Fixed a server crash when creating a `PRIMARY KEY` for a table, if the table contained a `BIT` column. (Bug#9571)

- Warning message from `GROUP_CONCAT()` did not always indicate correct number of lines. (Bug#8681)

- The commit count cache for `NDB` was not properly invalidated when deleting a record using a cursor. (Bug#8585)

- Fixed option-parsing code for the embedded server to understand `K`, `M`, and `G` suffixes for the `net_buffer_length` and `max_allowed_packet` options. (Bug#9472)

- Selecting a `BIT` column failed if the binary client/server protocol was used. (Bug#9608)

- Fixed a permissions problem whereby information in `INFORMATION_SCHEMA` could be exposed to a user with insufficient privileges. (Bug#7214)

- An error now occurs if you try to insert an invalid value via a stored procedure in `STRICT` mode. (Bug#5907)

- Link with `libsupc++` on Fedora Core 3 to get language support functions. (Bug#6554)

- The value of the `CHARACTER_MAXIMUM_LENGTH` and `CHARACTER_OCTET_LENGTH` columns of the `INFORMATION_SCHEMA.COLUMNS` table must be `NULL` for numeric columns, but were not. (Bug#9344)

- `DROP TABLE` did not drop triggers that were defined for the table. `DROP DATABASE` did not drop triggers in the database. (Bug#5859, Bug#6559)

- `CREATE OR REPLACE VIEW` and `ALTER VIEW` now require the `CREATE VIEW` and `DROP` privileges, not `CREATE VIEW` and `DELETE`. (`DELETE` is a row-level privilege, not a table-level privilege.) (Bug#9260)

- Some user variables were not being handled with ``implicit'' coercibility. (Bug#9425)

- Setting the `max_error_count` system variable to 0 resulted in a setting of 1. (Bug#9072)

- Fixed a collation coercibility problem that caused a union between binary and non-binary columns to fail. (Bug#6519)

- Fixed a bug in division of floating point numbers. It could cause nine zeroes (`000000000`) to be inserted in the middle of the quotient. (Bug#9501)

- `INFORMATION_SCHEMA` tables had an implicit upper limit for the number of rows. As a result, not all data could be returned for some queries. (Bug#9317)

- Fixed a problem with the `tee` command in mysql that resulted in mysql crashing. (Bug#8499)

- `CAST()` now produces warnings when casting a wrong `INTEGER` and `CHAR` values. This also applies to implicite `string` to `number` casts. (Bug#5912)

- `ALTER TABLE` now fails in `STRICT` mode if generates warnings.

- Using `CONVERT('0000-00-00',date)` or `CAST('0000-00-00' as date)` in `TRADITIONAL` mode now produces a warning. (Bug#6145)

- Inserting a zero date in a `DATE`, `DATETIME` or `TIMESTAMP` column during `TRADITIONAL` mode now produces an error. (Bug#5933)

- Inserting a zero date into a `DATETIME` column in `TRADITIONAL` mode now produces an error.

- `STR_TO_DATE()` now produces errors in strict mode (and warnings otherwise) when given an illegal argument. (Bug#5902)

- Fixed a problem with `ORDER BY` that sometimes caused incorrect sorting of `utf8` data. (Bug#9309)

- Fixed server crash resulting from queries that combined `SELECT DISTINCT`, `SUM()`, and `ROLLUP`. (Bug#8615)

- Incorrect results were returned from queries that combined `SELECT DISTINCT`, `GROUP BY` , and `ROLLUP`. (Bug#8616)

- Too many rows were returned from queries that combined `ROLLUP` and `LIMIT` if `SQL_CALC_FOUND_ROWS` was given. (Bug#8617)

- If on replication master a `LOAD DATA INFILE` is interrupted in the middle (integrity constraint violation, killed connection...), the slave used to skip this `LOAD DATA INFILE` entirely, thus missing some changes if this command permanently inserted/updated some table records before being interrupted. This is now fixed. (Bug#3247)

### C.1.4. Changements de la version 5.0.3 (23 mars 2005 : Beta)

Note : This Beta release, as any other pre-production release, should not be installed on ``production'' level systems or systems with critical data. It is good practice to back up your data before installing any new version of software. Although MySQL has done its best to ensure a high level of quality, protect your data by making a backup as you would for any software beta release.

Fonctionnalités ajoutées ou modifiées :

- New privilege `CREATE USER` was added.

- Security improvement : The server creates `.frm`, `.MYD`, `.MYI`, `.MRG`, `.ISD`, and `.ISM` table files only if a file with the same name does not already exist. Thanks to Stefano Di Paola `<stefano.dipaola@wisec.it>` for finding and informing us about this issue. (CAN-2005-0711)

- Security improvement : User-defined functions should have at least one symbol defined in addition to the `xxx` symbol that corresponds to the main `xxx()` function. These auxiliary symbols correspond to the `xxx_init()`, `xxx_deinit()`, `xxx_reset()`, `xxx_clear()`, and `xxx_add()` functions. mysqld by default no longer loads UDFs unless they have at least one auxiliary symbol defined in addition to the main symbol. The `--allow-suspicious-udfs` option controls whether UDFs that have only an `xxx` symbol can be loaded. By default, the option is off. `mysqld` also checks UDF filenames when it reads them from the `mysql.func` table and rejects those that contain directory pathname separator characters. (It already checked names as given in `CREATE FUNCTION` statements.) See Section 27.2.3.1, « Fonctions utilisateur : appeler des fonctions simples », Section 27.2.3.2, « Appeler des fonctions utilisateurs pour les groupements », and Section 27.2.3.6, « Précautions à prendre avec les fonctions utilisateur ». Thanks to Stefano Di Paola `<stefano.dipaola@wisec.it>` for finding and informing us about this issue. (CAN-2005-0709, CAN-2005-0710)

- Support for the `ISAM` storage engine has been removed. If you have `ISAM` tables, you should convert them before upgrading. See Section 2.6.1, « Passer en de version 4.1 en version 5.0 ».

- Support for `RAID` options in `MyISAM` tables has been removed. If you have tables that use these options, you should convert them before upgrading. See Section 2.6.1, « Passer en de version 4.1 en version 5.0 ».

- Added support for `AVG(DISTINCT)`.

- `ONLY_FULL_GROUP_BY` no longer is included in the `ANSI` composite SQL mode. (Bug#8510)

- mysqld_safe will create the directory where the UNIX socket file is to be located if the directory does not exist. This applies only to the last component of the directory pathname. (Bug#8513)

- The coercibility for the return value of functions such as `USER()` or `VERSION()` now is ``system constant'' rather than ``implicit.'' This makes these functions more coercible than column values so that comparisons of the two do not result in `Illegal mix of collations` errors. `COERCIBILITY()` was modified to accommodate this new coercibility value. See Section 12.8.3, « Fonctions d'informations ».

- User variable coercibility has been changed from ``coercible'' to ``implicit.'' That is, user variables have the same coercibility as column values.

- Boolean full-text phrase searching now requires only that matches contain exactly the same words as the phrase and in the same order. Non-word characters no longer need match exactly.

- `CHECKSUM TABLE` returns a warning for non-existing tables. The checksum value remains `NULL` as before. (Bug#8256)

- The server now includes a timestamp in the `Ready for connections` message that is written to the error log at startup. (Bug#8444)

- Added `SQL_NOTES` session variable to cause `Note`-level warnings not to be recorded. (Bug#6662)

- Allowed the service-installation command for Windows servers to specify a single option other than `--defaults-file` following the service name. This is for compatibility with MySQL 4.1. (Bug#7856)

- InnoDB : Upgrading from 4.1 : The sorting order for end-space in `TEXT` columns for InnoDB tables has changed. Starting from 5.0.3, InnoDB compares `TEXT` columns as space-padded at the end. If you have a non-unique index on a `TEXT` column, you should run `CHECK TABLE` on it, and run `OPTIMIZE TABLE` if the check reports errors. If you have a `UNIQUE INDEX` on a `TEXT` column, you should rebuild the table with `OPTIMIZE TABLE`.

- `InnoDB` : Commit after every 10,000 copied rows when executing `ALTER TABLE`, `CREATE INDEX`, `DROP INDEX` or `OPTIMIZE TABLE`. This makes it much faster to recover from an aborted operation.

- Added `VAR_POP()` and `STDDEV_POP()` as standard SQL aliases for the `VARIANCE()` and `STDDEV()` functions that compute population variance and standard deviation. Added new `VAR_SAMP()` and `STDDEV_SAMP()` functions to compute sample variance and standard deviation. (Bug#3190)

- Fixed a problem with out-of-order packets being sent (`ERROR` after `OK` or `EOF`) following a `KILL QUERY` statement. (Bug#6804)

- Retrieving from a view defined as a `SELECT` that mixed `UNION ALL` and `UNION DISTINCT` resulted in a different result than retrieving from the original `SELECT`. (Bug#6565)

- Fixed a problem with non-optimal `index_merge` query execution plans being chosen on IRIX. (Bug#8578)

- `BIT` in column definitions now is a distinct data type; it no longer is treated as a synonym for `TINYINT(1)`.

- Bit-field values can be written using `b'`value`'` notation. `value` is a binary value written using 0s and 1s.

- From the Windows distribution, predefined accounts without passwords for remote users ("root@%", "@%") were removed (other distributions never had them).

- Added `mysql_library_init()` and `mysql_library_end()` as synonyms for the `mysql_server_init()` and `mysql_server_end()` C API functions. `mysql_library_init()` and `mysql_library_end()` are `#define` symbols, but the names more clearly indicate that they should be called when beginning and ending use of a MySQL C API library no matter whether the application uses `libmysqlclient` or `libmysqld`. (Bug#6149)

- `SHOW COLUMNS` now displays `NO` rather than blank in the `Null` output column if the corresponding table column cannot be `NULL`.

- Changed XML format for mysql from `<`col_name`>`col_value`</`col_name`>` to `<field name="`col_name`">`col_value`</field>` to allow for proper encoding of column names that are not legal as element names. (Bug#7811)

- Added `--innodb-checksums` and `--innodb-doublewrite` options for mysqld.

- Added `--large-pages` option for mysqld.

- Added `multi_read_range` system variable.

- `SHOW DATABASES`, `SHOW TABLES`, `SHOW COLUMNS`, and so forth display information about the `INFORMATION_SCHEMA` database. Also, several `SHOW` statements now accept a `WHERE` clause specifying which output rows to display. See Chapitre 22, La base de données d'informations `INFORMATION_SCHEMA`.

- Added the `CREATE ROUTINE` and `ALTER ROUTINE` privileges, and made the `EXECUTE` privilege operational.

- InnoDB : Corrected a bug in the crash recovery of `ROW_FORMAT=COMPACT` tables that caused corruption. (Bug#7973) There may still be bugs in the crash recovery, especially in `COMPACT` tables.

- When the `MyISAM` storage engine detects corruption of a `MyISAM` table, a message describing the problem now is written to the error log.

- InnoDB : When MySQL/InnoDB is compiled on Mac OS X 10.2 or earlier, detect the operating system version at run time and use the `fcntl()` file flush method on Mac OS X versions 10.3 and later. Apple had disabled `fsync()` in Mac OS X for internal disk drives, which caused corruption at power outages.

- InnoDB : Implemented fast `TRUNCATE TABLE`. The old approach (deleting rows one by one) may be used if the table is being referenced by foreign keys. (Bug#7150)

- Added `cp932` (SJIS for Windows Japanese) and `eucjpms` (UJIS for Windows Japanese) character sets.

- Added several `InnoDB` status variables. See Section 5.2.4, « Variables de statut du serveur ».

- Added the `FEDERATED` storage engine. See Section 14.6, « Le moteur de table `FEDERATED` ».

- `SHOW CREATE TABLE` now uses `USING `index_type`` rather than `TYPE `index_type`` to specify an index type. (Bug#7233)

- InnoDB now supports a fast `TRUNCATE TABLE`. One visible change from this is that auto-increment values for this table are reset on `TRUNCATE`.

- Added an `error` member to the `MYSQL_BIND` data structure that is used in the C API for prepared statements. This member is used for reporting data truncation errors. Truncation reporting is enabled via the new `MYSQL_REPORT_DATA_TRUNCATION` option for the `mysql_options()` C API function.

- API change : the `reconnect` flag in the `MYSQL` structure is now set to 0 by `mysql_real_connect()`. Only those client programs which didn't explicitly set this flag to 0 or 1 after `mysql_real_connect()` experience a change. Having automatic reconnection enabled by default was considered too dangerous (after reconnection, table locks, temporary tables, user and session variables are lost).

- `FLUSH TABLES WITH READ LOCK` is now killable while it's waiting for running `COMMIT` statements to finish.

- `MEMORY` (`HEAP`) can have `VARCHAR()` fields.

- `VARCHAR` columns now remember end space. A `VARCHAR()` column can now contain up to 65535 bytes. For more details, see Section C.1, « Changements de la version 5.0.0 (Développement) ». If the table handler doesn't support the new `VARCHAR` type, then it's converted to a `CHAR` column. Currently this happens for `NDB` tables.

- InnoDB : Introduced a compact record format that does not store the number of columns or the lengths of fixed-size columns. The old format can be requested by specifying `ROW_FORMAT=REDUNDANT`. The new format (`ROW_FORMAT=COMPACT`) is the default. The new format typically saves 20 % of disk space and memory.

- InnoDB : Setting the initial `AUTO_INCREMENT` value for an `InnoDB` table using `CREATE TABLE ... AUTO_INCREMENT = `n`` now works, and `ALTER TABLE ... AUTO_INCREMENT = `n`` resets the current value.

- `Seconds_Behind_Master` is `NULL` (which means ``unknown'') if the slave SQL thread is not running, or if the slave I/O thread is not running or not connected to master. It is zero if the SQL thread has caught up to the I/O thread. It no longer grows indefinitely if the master is idle.

- The MySQL server aborts immediately instead of simply issuing a warning if it is started with the `--log-bin` option but cannot initialize the binary log at startup (that is, an error occurs when writing to the binary log file or binary log index file).

- The binary log file and binary log index file now are handled the same way as `MyISAM` tables when there is a ``disk full'' or ``quota exceeded'' error. See Section A.4.3, « Comment MySQL gère un disque plein ».

- The MySQL server now aborts when started with option `--log-bin-index` and without `--log-bin`, and when started with `--log-slave-updates` and without `--log-bin`.

- If the MySQL server is started without an argument to `--log-bin` and without `--log-bin-index`, thus not providing a name for the binary log index file, a warning is issued because MySQL falls back to using the hostname for that name, and this is prone to replication issues if the server's hostname's gets changed later. See Section 1.5.7.4, « Bugs connus / limitations de MySQL ».

- Added account-specific `MAX_USER_CONNECTIONS` limit, which allows you to specify the maximum number of concurrent connections for the account. Also, all limited resources now are counted per account (instead of being counted per user + host pair as it was before). Use the `--old-style-user-limits` option to get the old behavior.

- InnoDB : A shared record lock (`LOCK_REC_NOT_GAP`) is now taken for a matching record in the foreign key check because inserts can be allowed into gaps.

- InnoDB : Relaxed locking in INSERT...SELECT, single table UPDATE...SELECT and single table DELETE...SELECT clauses when innobase_locks_unsafe_for_binlog is used and isolation level of the transaction is not serializable. `InnoDB` uses consistent read in these cases for a selected table.

- Added a new global system variable `slave_transaction_retries` : if the replication slave SQL thread fails to execute a transaction because of an `InnoDB` deadlock or exceeded InnoDB's `innodb_lock_wait_timeout` or NDBCluster's `TransactionDeadlockDetectionTimeout` or `TransactionInactiveTimeout`, it automatically retries `slave_transaction_retries` times before stopping with an error. The default is 10. (Bug#8325)

- When a client releases a user-level lock, `DO RELEASE_LOCK()` will not be written to the binary log anymore (this makes the binary log smaller); as a counterpart, the slave does not actually take the lock when it executes `GET_LOCK()`. This is mainly an optimization and should not affect existing setups. (Bug#7998)

- The way the character set information is stored into the binary log was changed, so that it's now possible to have a replication master and slave running with different global character sets. A drawback is that replication from 5.0.3 masters to pre-5.0.3 slaves is impossible.

- The `LOAD DATA` statement was extended to support user variables in the target column list, and an optional `SET` clause. Now one can perform some transformations on data after they have been read and before they are inserted into the table. For example :

      LOAD DATA INFILE 'file.txt'
        INTO TABLE t1
        (column1, @var1)
        SET column2 = @var1/100;

  Also, replication of `LOAD DATA` was changed, so you can't replicate such statements from a 5.0.3 master to pre-5.0.3 slaves.

Bogues corrigés :

- If a `MyISAM` table on Windows had `INDEX DIRECTORY` or `DATA DIRECTORY` table options, mysqldump dumped the directory pathnames with single-backslash pathname separators. This would cause syntax errors when importing the dump file. mysqldump now changes ‘`\`’ to ‘`/`’ in the pathnames on Windows. (Bug#6660)

- `mysql_fix_privilege_tables` now fixes that the `mysql` privilege tables can be used in MySQL 4.1. This allows one to easily downgrade to 4.1 or run MySQL 5.0 and 4.1 with the same privilege files for testing purposes.

- Fixed bug creating user with GRANT fails with password but works without, (Bug#7905)

- mysqldump misinterpreted ‘`_`’ and ‘`%`’ characters in the names of tables to be dumped as wildcard characters. (Bug#9123)

- The definition of the enumeration-valued `sql_mode` column of the `mysql.proc` table was missing some of the current allowable SQL modes, so stored routines would not necessarily execute with the SQL mode in effect at the time of routine definition. (Bug#8902)

- `REPAIR TABLE` did not invalidate query results in the query cache that were generated from the table. (Bug#8480)

- In strict or traditional SQL mode, too-long string values assigned to string columns (`CHAR`, `VARCHAR`, `BINARY`, `VARBINARY`, `TEXT`, or `BLOB`) were correctly truncated, but the server returned an SQLSTATE value of `01000` (should be `22001`). (Bug#6999, Bug#9029)

- Stored functions that used cursors could return incorrect results. (Bug#8386)

- `AES_DECRYPT(`col_name`,`key`)` could fail to return `NULL` for invalid values in `col_name`, if `col_name` was declared as `NOT NULL`. (Bug#8669)

- Ordering by unsigned expression (more complex than a column reference) was treating the value as signed, producing incorrectly sorted results. (Bug#7425)

- `HAVING` was treating unsigned columns as signed. (Bug#7425)

- Fixed a problem with boolean full-text searches on `utf8` columns where a double quote in the search string caused a server crash. (Bug#8351)

- For a query with both `GROUP BY` and `COUNT(DISTINCT)` clauses and a `FROM` clause with a subquery, `NULL` was returned for any `VARCHAR` column selected by the subquery. (Bug#8218)

- Fixed a bug in `TRUNCATE`, which did not work within stored procedures. A workaround has been made so that within stored procedures, `TRUNCATE` is executed like `DELETE`. This was necessary because `TRUNCATE` is implicitly locking tables. (Bug#8850)

- Fixed an optimizer bug that caused incorrectly ordered result from a query that used a `FULLTEXT` index to retrieve rows and there was another index that was usable for `ORDER BY`. For such a query, `EXPLAIN` showed `fulltext` join type, but regular (not `FULLTEXT`) index in the `Key` column. (Bug#6635)

- If `SELECT DISTINCT` named an index column multiple times in the select list, the server tried to access different key fields for each instance of the column, which could result in a crash. (Bug#8532)

- For a stored function that refers to a given table, invoking the function while selecting from the same table resulted in a server crash. (Bug#8405)

- Comparison of a `DECIMAL` column containing `NULL` to a subquery that produced `DECIMAL` values resulted in a server crash. (Bug#8397)

- The `--set-character-set` option for myisamchk was changed to `--set-collation`. The value needed for specifying how to sort indexes is a collation name, not a character set name. (Bug#8349)

- Hostname matching didn't work if a netmask was specified for table-specific privileges. (Bug#3309)

- Corruption of `MyISAM` table indexes could occur with `TRUNCATE TABLE` if the table had already been opened. For example, this was possible if the table had been opened implicitly by selecting from a `MERGE` table that mapped to the `MyISAM` table. The server now issues an error message for `TRUNCATE TABLE` under these conditions. (Bug#8306)

- Setting the connection collation to a value different from the server collation followed by a `CREATE TABLE` statement that included a quoted default value resulted in a server crash. (Bug#8235)

- Fixed handling of table-name matching in mysqlhotcopy to accommodate `DBD::mysql` 2.9003 and up (which implement identifier quoting). (Bug#8136)

- Selecting from a view defined as a join caused a server crash if the query cache was enabled. (Bug#8054)

- Results in the query cache generated from a view were not properly invalidated after `ALTER VIEW` or `DROP VIEW` on that view. (Bug#8050)

- `FOUND_ROWS()` returned an incorrect value after a `SELECT SQL_CALC_FOUND_ROWS DISTINCT` statement that selected constants and included `GROUP BY` and `LIMIT` clauses. (Bug#7945)

- Selecting from an `INFORMATION_SCHEMA` table combined with a subselect on an `INFORMATION_SCHEMA` table caused an error with the message `Table `tbl_name` is corrupted`. (Bug#8164)

- Fixed a problem with equality propagation optimization for prepared statements and stored procedures that caused a server crash upon re-execution of the prepared statement or stored procedure. (Bug#8115, Bug#8849)

- `LEFT OUTER JOIN` between an empty base table and a view on an empty base table caused a server crash. (Bug#7433)

- Use of `GROUP_CONCAT()` in the select list when selecting from a view caused a server crash. (Bug#7116)

- Use of a view in a correlated subquery that contains `HAVING` but no `GROUP BY` caused a server crash. (Bug#6894)

- Handling by `mysql_list_fields()` of references to stored functions within views was incorrect and could result in a server crash. (Bug#6814)

- mysqldump now avoids writing `SET NAMES` to the dump output if the server is older than version 4.1 and would not understand that statement. (Bug#7997)

- Fixed problems when selecting from a view that had an `EXISTS` or `NOT EXISTS` subquery. Selecting columns by name caused a server crash. With `SELECT *`, a crash did not occur, but columns in outer query were not resolved properly. (Bug#6394)

- DDL statements for views were not being written to the binary log (and thus not subject to replication). (Bug#4838)

- The `CHAR()` function was not ignoring `NULL` arguments, contrary to the documentation. (Bug#6317)

- Creating a table using a name containing a character that is illegal in `character_set_client` resulted in the character being stripped from the name and no error. The character now is considered an error. (Bug#8041)

- Fixed a problem with the Cyrillic letters I and SHORT I being treated the same by the `utf8_general_ci` collation. (Bug#8385)

- Some `INFORMATION_SCHEMA` columns that contained catalog identifiers were of type `LONGTEXT`. These were changed to `VARCHAR(`N``, where `N` is the appropriate maximum identifier length. (Bug#7215)

- Some `INFORMATION_SCHEMA` columns that contained timestamp values were of type `VARBINARY`. These were changed to `TIMESTAMP`. (Bug#7217)

- An expression that tested a case-insensitive character column against string constants that differed in lettercase could fail because the constants were treated as having a binary collation. (For example, `WHERE city='London' AND city='london'` could fail.) (Bug#7098, Bug#8690)

- The output of the `STATUS` (`\s`) command in mysql had the values for the server and client character sets reversed. (Bug#7571)

- If the slave was running with `--replicate-*-table` options which excluded one temporary table and included another, and the two tables were used in a single `DROP TEMPORARY TABLE IF EXISTS` statement, as the ones the master automatically writes to its binary log upon client's disconnection when client has not explicitly dropped these, the slave could forget to delete the included replicated temporary table. Only the slave needs to be upgraded. (Bug#8055)

- When setting integer system variables to a negative value with `SET VARIABLES`, the value was treated as a positive value modulo 2^32. (Bug#6958)

- Corrected a problem with references to `DUAL` where statements such as `SELECT 1 AS a FROM DUAL` would succeed but statements such as `SELECT 1 AS a FROM DUAL LIMIT 1` would fail. (Bug#8023)

- Fixed a server crash caused by `DELETE FROM `tbl_name` ... WHERE ... ORDER BY `tbl_name`.`col_name`` when the `ORDER BY` column was qualified with the table name. (Bug#8392)

- Fixed a bug in `MATCH ... AGAINST` in natural language mode that could cause a server crash if the `FULLTEXT` index was not used in a join (`EXPLAIN` did not show `fulltext` join mode) and the search query matched no rows in the table (Bug#8522).

- `InnoDB` : Honor the `--tmpdir` startup option when creating temporary files. Previously, `InnoDB` temporary files were always created in the temporary directory of the operating system. On Netware, `InnoDB` will continue to ignore `--tmpdir`. (Bug#5822)

- Platform and architecture information in version information produced for `--version` option on Windows was always `Win95/Win98 (i32)`. More accurately determine platform as `Win32` or `Win64` for 32-bit or 64-bit Windows, and architecture as `ia32` for x86, `ia64` for Itanium, and `axp` for Alpha. (Bug#4445)

- If multiple semicolon-separated statements were received in a single packet, they were written to the binary log as a single event rather than as separate per-statement events. For a server serving as a replication master, this caused replication to fail when the event was sent to slave servers. (Bug#8436)

- Fixed `LOAD INDEX` statement to actually load index in memory. (Bug#8452)

- Fixed a failure of multiple-table updates to replicate properly on slave servers when `--replicate-*-table` options had been specified. (Bug#7011)

- Fixed failure of `CREATE TABLE ... LIKE` Windows when the source or destination table was located in a symlinked database directory. (Bug#6607)

- With `lower_case_table_names` set to 1, mysqldump on Windows could write the same table name in different lettercase for different SQL statements. Fixed so that consistent lettercase is used. (Bug#5185)

- mysqld_safe now understands the `--help` option. Previously, it ignored the option and attempted to start the server anyway. (Bug#7931)

- Fixed problem in `NO_BACKSLASH_ESCAPES` SQL mode for strings that contained both the string quoting character and backslash. (Bug#6368)

- Fixed some portability issues with overflow in floating point values.

- Prepared statements now gives warnings on prepare.

- Fixed bug in prepared statements with `SUM(DISTINCT...)`.

- Fixed bug in prepared statements with `OUTER JOIN`.

- Fixed a bug in `CONV()` function returning unsigned `BIGINT` number (third argument is positive, and return value does not fit in 32 bits). (Bug#7751)

- Fixed a failure of the `IN()` operator to return correct result if all values in the list were constants and some of them were using substring functions, for example, `LEFT()`, `RIGHT()`, or `MID()`. (Bug#7716)

- Fixed a crash in `CONVERT_TZ()` function when its second or third argument was from a `const` table (see Section 7.2.1, « Syntaxe de `EXPLAIN` (Obtenir des informations sur les `SELECT`) »). (Bug#7705)

- Fixed a problem with calculation of number of columns in row comparison against subquery. (Bug#8020)

- Fixed erroneous output resulting from `SELECT DISTINCT` combined with a subquery and `GROUP BY`. (Bug#7946)

- Fixed server crash in comparing a nested row expression (for example `row(1,(2,3))`) with a subquery. (Bug#8022)

- Fixed server crash resulting from certain correlated subqueries with forward references (references to an alias defined later in the outer query). (Bug#8025)

- Fixed server crash resulting from re-execution of prepared statements containing subqueries. (Bug#8125)

- Fixed a bug where `ALTER TABLE` improperly would accept an index on a `TIMESTAMP` column that `CREATE TABLE` would reject. (Bug#7884)

- `SHOW CREATE TABLE` now reports `ENGINE=MEMORY` rather than `ENGINE=HEAP` for a `MEMORY` table (unless the `MYSQL323` SQL mode is enabled). (Bug#6659)

- Fixed a bug where the use of `GROUP_CONCAT()` with `HAVING` caused a server crash. (Bug#7769)

- Fixed a bug where comparing the result of a subquery to a non-existent column caused a server crash on Windows. (Bug#7885)

- Fixed a bug in a combination of `-not` and `trunc*` operators of full-text search. Using more than one truncated negative search term, was causing empty result set.

- InnoDB : Corrected the handling of trailing spaces in the `ucs2` character set. (Bug#7350, Bug#8771)

- InnoDB : Use native `tmpfile()` function on Netware. All InnoDB temporary files are created under `sys:\tmp`. Previously, InnoDB temporary files were never deleted on Netware.

- Fixed a bug in `max_heap_table_size` handling, that resulted in `Table is full` error when the table was still smaller than the limit. (Bug#7791).

- Fixed a symlink vulnerability in the mysqlaccess script. Reported by Javier Fernandez-Sanguino Pena and Debian Security Audit Team. (CAN-2005-0004)

- Fixed a bug that caused server crash if some error occured during filling of temporary table created for derived table or view handling. (Bug#7413)

- Fixed a bug which caused server crash if query containing `CONVERT_TZ()` function with constant arguments was prepared. (Bug#6849)

- Prevent adding `CREATE TABLE .. SELECT` query to the binary log when the insertion of new records partially failed. (Bug#6682)

- Fixed a bug which caused a crash when only the slave I/O thread was stopped and started. (Bug#6148)

- Giving mysqld a `SIGHUP` caused it to crash.

- Changed semantics of `CREATE/ALTER/DROP DATABASE` statements so that replication of `CREATE DATABASE` is possible when using `--binlog-do-db` and `--binlog-ignore-db`. (Bug#6391)

- A sequence of `BEGIN` (or `SET AUTOCOMMIT=0`), `FLUSH TABLES WITH READ LOCK`, transactional update, `COMMIT`, `FLUSH TABLES WITH READ LOCK` could hang the connection forever and possibly the MySQL server itself. This happened for example when running the `innobackup` script several times. (Bug#6732)

- mysqlbinlog did not print `SET PSEUDO_THREAD_ID` statements in front of `LOAD DATA INFILE` statements inserting into temporary tables, thus causing potential problems when rolling forward these statements after restoring a backup. (Bug#6671)

- InnoDB : Fixed a bug no error message for ALTER with InnoDB and AUTO_INCREMENT (Bug#7061). `InnoDB` now supports `ALTER TABLE...AUTO_INCREMENT = x` query to set auto increment value for a table.

- Made the MySQL server accept executing `SHOW CREATE DATABASE` even if the connection has an open transaction or locked tables; refusing it made mysqldump --single-transaction sometimes fail to print a complete `CREATE DATABASE` statement for some dumped databases. (Bug#7358)

- Fixed that, when encountering a ``disk full'' or ``quota exceeded'' write error, `MyISAM` sometimes didn't sleep and retry the write, thus resulting in a corrupted table. (Bug#7714)

- Fixed that `--expire-log-days` was not honored if using only transactions. (Bug#7236)

- Fixed that a slave could crash after replicating many `ANALYZE TABLE`, `OPTIMIZE TABLE`, or `REPAIR TABLE` statements from the master. (Bug#6461, Bug#7658)

- mysqlbinlog forgot to add backquotes around the collation of user variables (causing later parsing problems as `BINARY` is a reserved word). (Bug#7793)

- Ensured that mysqldump --single-transaction sets its transaction isolation level to `REPEATABLE READ` before proceeding (otherwise if the MySQL server was configured to run with a default isolation level lower than `REPEATABLE READ` it could give an inconsistent dump). (Bug#7850)

- Fixed that when using the `RPAD()` function (or any function adding spaces to the right) in a query that had to be resolved by using a temporary table, all resulting strings had rightmost spaces removed (i.e. `RPAD()` did not work) (Bug#4048)

- Fixed that a 5.0.3 slave can connect to a master < 3.23.50 without hanging (the reason for the hang is a bug in these quite old masters -- `SELECT @@unknown_var` hangs them -- which was fixed in MySQL 3.23.50). (Bug#7965)

- InnoDB : Fixed a deadlock without any locking, simple select and update (Bug#7975). `InnoDB` now takes an exclusive lock when `INSERT ON DUPLICATE KEY UPDATE` is checking duplicate keys.

- Fixed a bug where MySQL was allowing concurrent updates (inserts, deletes) to a table if binary logging is enabled. Changed to ensure that all updates are executed in a serialized fashion, because they are executed serialized when binlog is replayed. (Bug#7879)

- Fixed a rare race condition which could lead to `FLUSH TABLES WITH READ LOCK` hanging. (Bug#8682)

- Fixed a bug that caused the slave to stop on statements that produced an error on the master. (Bug#8412)

### C.1.5. Changements de la version 5.0.2 (1er Décembre 2004)

Fonctionnalités ajoutées ou modifiées :

- The `SCHEMA` and `SCHEMAS` keywords now are accepted as synonyms for `DATABASE` and `DATABASES`.

- Added initial support for rudimentary triggers.

- Added basic support for read-only server side cursors.

- Added `--start-datetime`, `--stop-datetime`, `--start-position`, `--stop-position` options to mysqlbinlog (makes point-in-time recovery easier).

- Made the MySQL server not react to signals `SIGHUP` and `SIGQUIT` on Mac OS X 10.3. This is needed because under this OS, the MySQL server receives lots of these signals (reported as Bug#2030).

- New `--auto-increment-increment` and `--auto-increment-offset` startup options. These allow you to set up a server to generate auto-increment values that don't conflict with another server.

- MySQL now by default will check dates and only allow fully correct dates. If you want to MySQL to behave as default, you should enable the new `ALLOW_INVALID_DATES` SQL mode.

- Added `STRICT_TRANS_TABLES`, `STRICT_ALL_TABLES`, `NO_ZERO_IN_DATE`, `NO_ZERO_DATE`, `ERROR_FOR_DIVISION_BY_ZERO`, and `TRADITIONAL` SQL modes. The `TRADITIONAL` mode is shorthand for all the preceding modes. When using mode `TRADITIONAL`, MySQL generates an error if you try to insert a wrong value in a column. It does not adjust the value to the closest possible legal value.

- MySQL now remembers which columns were declared to have default values. In `STRICT_TRANS_TABLES`/`STRICT_ALL_TABLES` mode, you now get an error if you do an `INSERT` without specifying all columns that don't have a default value. A side effect of this is that when you do `SHOW CREATE` for a new table, you will no longer see a `DEFAULT` value for a column for which you didn't specify a default value.

- The compilation flag `DONT_USE_DEFAULT_FIELDS` was removed because you can get the same behavior by setting the `sql_mode` system variable to `STRICT_TRANS_TABLES`.

- We now detect too-large floating point numbers during statement parsing and generate an error messages for them.

- Renamed the `sql_updatable_view_key` system variable to `updatable_views_with_limit`. This variable now can have only two values:

  - `1` or `YES`: Don't issue an error message (warning only) if a VIEW without presence of a key in the underlying table is used in queries with a `LIMIT` clause for updating. (This is the default value.)

  - `0` or `NO`: Prohibit update of a VIEW, which does not contain a key in the underlying table and the query uses a `LIMIT` clause (usually get from GUI tools).

- Reverted output format of `SHOW TABLES` to old pre-5.0.1 format that did not include a table type column. To get the additional column that lists the table type, use `SHOW FULL TABLES` now.

- The mysql_fix_privilege_tables script now initializes the global `CREATE VIEW` and `SHOW VIEW` privileges in the `user` table to the value of the `CREATE` privilege in that table.

- If the server finds that the `user` table has not been upgraded to include the view-related privilege columns, it treats each account as having view privileges that are the same as its `CREATE` privilege.

Bogues corrigés :

- Fixed that mysqlbinlog --read-from-remote-server sometimes couldn't accept two binary logfiles on the command line. (Bug#4507)

- Fixed that mysqlbinlog --position --read-from-remote-server had incorrect `# at` lines. (Bug#4506)

- Fixed that `CREATE TABLE ... TYPE=HEAP ... AS SELECT...` caused replication slave to stop. (Bug#4971)

- Fixed that `mysql_options(...,MYSQL_OPT_LOCAL_INFILE,...)` failed to disable `LOAD DATA LOCAL INFILE`. (Bug#5038)

- Fixed that `disable-local-infile` option had no effect if client read it from a configuration file using `mysql_options(...,MYSQL_READ_DEFAULT,...)`. (Bug#5073)

- Fixed that `SET GLOBAL SYNC_BINLOG` did not work on some platforms (Mac OS X). (Bug#5064)

- Fixed that mysql-test-run failed on the `rpl_trunc_binlog` test if running test from the installed (the target of 'make install') directory. (Bug#5050)

- Fixed that mysql-test-run failed on the `grant_cache` test when run as Unix user 'root'. (Bug#4678)

- Fixed an unlikely deadlock which could happen when using `KILL`. (Bug#4810)

- Fixed a crash when one connection got `KILL`ed while it was doing `START SLAVE`. (Bug#4827)

- Made `FLUSH TABLES WITH READ LOCK` block `COMMIT` if server is running with binary logging; this ensures that the binary log position can be trusted when doing a full backup of tables and the binary log. (Bug#4953)

- Fixed that the counter of an `auto_increment` column was not reset by `TRUNCATE TABLE` is the table was a temporary one. (Bug#5033)

- Fixed slave SQL thread so that the `SET COLLATION_SERVER...` statements it replicates don't advance its position (so that if it gets interrupted before the actual update query, it will later redo the `SET`). (Bug#5705)

- Fixed that if the slave SQL thread found a syntax error in a query (which should be rare, as the master parsed it successfully), it stops. (Bug#5711)

- Fixed that if a write to a MyISAM table fails because of a full disk or an exceeded disk quota, it prints a message to the error log every 10 minutes, and waits until disk becomes free. (Bug#3248)

- Fixed problem introduced in 4.0.21 where a connection starting a transaction, doing updates, then `FLUSH TABLES WITH READ LOCK`, then `COMMIT`, would cause replication slaves to stop complaing about error 1223. Bug surfaced when using the InnoDB `innobackup` script. (Bug#5949)

### C.1.6. Changements de la version 5.0.1 (pas encore publiée)

Fonctionnalité ajoutée ou modifiée :

- For replication of `MEMORY` (`HEAP`) tables: Made the master automatically write a `DELETE FROM` statement to its binary log when a `MEMORY` table is opened for the first time since master's startup. This is for the case where the slave has replicated a non-empty `MEMORY` table, then the master is shut down and restarted: the table is now empty on master; the `DELETE FROM` empties it on slave too. Note that even with this fix, between the master's restart and the first use of the table on master, the slave still has out-of-date data in the table. But if you use the `--init-file` option to populate the `MEMORY` table on the master at startup, it ensures that the failing time interval is zero. (Bug#2477)

- When a session having open temporary tables terminates, the statement automatically written to the binary log is now `DROP TEMPORARY TABLE IF EXISTS` instead of `DROP TEMPORARY TABLE`, for more robustness.

- The MySQL server now returns an error if `SET SQL_LOG_BIN` is issued by a user without the `SUPER` privilege (in previous versions it just silently ignored the statement in this case).

- Changed that when the MySQL server has binary logging disabled (that is, no `log-bin` option was used) then no transaction binlog cache is allocated for connections (this should save `binlog_cache_size` bytes of memory (32 kilobytes by default) for every connection).

- Added option `--replicate-same-server-id`.

Bogues corrigés :

- Strange results with index (x, y) ... WHERE x=val_1 AND y>=val_2 ORDER BY pk; (Bug#3155)

- Subquery and order by (Bug#3118)

- `ALTER DATABASE` caused the client to hang if the database did not exist. (Bug#2333)

- `SLAVE START` (which is a deprecated syntax, `START SLAVE` should be used instead) could crash the slave. (Bug#2516)

- Multiple-table `DELETE` statements were never replicated by the slave if there were any `replicate-*-table` options. (Bug#2527)

- The MySQL server did not report any error if the query (submitted through `mysql_real_query()` or `mysql_prepare()`) was terminated by garbage characters (which can happen if you pass a wrong `length` parameter to `mysql_real_query()` or `mysql_prepare()`); the result was that the garbage characters were written into the binary log. (Bug#2703)

- Replication: If a client connects to a slave server and issues an administrative statement for a table (for example, `OPTIMIZE TABLE` or `REPAIR TABLE`), this could sometimes stop the slave SQL thread. This does not lead to any corruption, but you must use `START SLAVE` to get replication going again. (Bug#1858)

- Made clearer the error message which one gets when an update is refused because of the `read-only` option. (Bug#2757)

- Fixed that `replicate-wild-*-table` rules apply to `ALTER DATABASE` when the table pattern is '%', like it is already the case for `CREATE DATABASE` and `DROP DATABASE`. (Bug#3000)

- Fixed that when a `Rotate` event is found by the slave SQL thread in the middle of a transaction, the value of `Relay_Log_Pos` in `SHOW SLAVE STATUS` remains correct. (Bug#3017)

- Corrected the master's binary log position that `InnoDB` reports when it is doing a crash recovery on a slave server. (Bug#3015)

- Changed the column `Seconds_Behind_Master` in `SHOW SLAVE STATUS` to never show a value of -1. (Bug#2826)

- Changed that when a `DROP TEMPORARY TABLE` statement is automatically written to the binlog when a session ends, the statement is recorded with an error code of value zero (this ensures that killing a `SELECT` on the master does not result in a superfluous error on the slave). (Bug#3063)

- Changed that when a thread handling `INSERT DELAYED` (also known as a `delayed_insert` thread) is killed, its statements are recorded with an error code of value zero (killing such a thread does not endanger replication, so we thus avoid a superfluous error on the slave). (Bug#3081)

- Fixed deadlock when two `START SLAVE` commands were run at the same time. (Bug#2921)

- Fixed that a statement never triggers a superfluous error on the slave, if it must be excluded given the `replicate-*` options. The bug was that if the statement had been killed on the master, the slave would stop. (Bug#2983)

- The `--local-load` option of `mysqlbinlog` now requires an argument.

- Fixed a segmentation fault when running `LOAD DATA FROM MASTER` after `RESET SLAVE`. (Bug#2922)

- `mysqlbinlog --read-from-remote-server` read all binary logs following the one that was requested. It now stops at the end of the requested file, the same was it does when reading a local binary log. (Bug#3204)

- Fixed `mysqlbinlog --read-from-remote-server` to print the exact positions of events in the "at #" lines. (Bug#3214)

- Fixed a rare error condition that caused the slave SQL thread spuriously to print the message `Binlog has bad magic number` and stop when it was not necessary to do so. (Bug#3401)

- Fixed `mysqlbinlog` not to forget to print a `USE` statement under rare circumstances where the binary log contained a `LOAD DATA INFILE` statement. (Bug#3415)

- Fixed a memory corruption when replicating a `LOAD DATA INFILE` when the master had version 3.23. (Bug#3422)

- Multiple-table `DELETE` statements were always replicated by the slave if there were some `replicate-*-ignore-table` options and no `replicate-*-do-table` options. (Bug#3461)

- Fixed a crash of the MySQL slave server when it was built with `--with-debug` and replicating itself. (Bug#3568)

- Fixed that in some replication error messages, a very long query caused the rest of the message to be invisible (truncated), by putting the query last in the message. (Bug#3357)

### C.1.7. Changements de la version 5.0.0 (22 décembre 2003 : Alpha)

Fonctionnalité ajoutée ou modifiée :

- The `KILL` statement now takes `CONNECTION` and `QUERY` modifiers. The first is the same as `KILL` with no modifier (it kills a given connection thread). The second kills only the statement currently being executed by the connection.

- Added `TIMESTAMPADD()` and `TIMESTAMPDIFF()` functions.

- Added `WEEK` and `QUARTER` values as `INTERVAL` arguments for the `DATE_ADD()` and `DATE_SUB()` functions.

- New binary log format that enables replication of these session variables: `sql_mode`, `SQL_AUTO_IS_NULL`, `FOREIGN_KEY_CHECKS` (which was already replicated since 4.0.14, but here it's done more efficiently and takes less space in the binary logs), `UNIQUE_CHECKS`. Other variables (like character sets, `SQL_SELECT_LIMIT`, ...) will be replicated in upcoming 5.0.x releases.

- Implemented Index Merge optimization for `OR` clauses. See Section 7.2.6, « Optimisation de combinaison d'index ».

- Basic support for stored procedures (SQL:2003 style). See Chapitre 19, Procédures stockées et fonctions.

- Added `SELECT INTO `list_of_vars``, which can be of mixed (that is, global and local) types. See Section 19.2.9.3, « Syntaxe de `SELECT ... INTO` ».

- Easier replication upgrade (5.0.0 masters can read older binary logs and 5.0.0 slaves can read older relay logs). See Section 6.5, « Compatibilité de la réplication entre les versions de MySQL » for more details). The format of the binary log and relay log is changed compared to that of MySQL 4.1 and older.

- Important note: If you upgrade to MySQL 4.1.1 or higher, it is difficult to downgrade back to 4.0 or 4.1.0! That is because, for earlier versions, `InnoDB` is not aware of multiple tablespaces.

Bogues corrigés :

## C.2. Changements de la version 4.1.x (Alpha)

Version 4.1 of the MySQL server includes many enhancements and new features. Binaries for this version are available for download at http://www.mysql.com/downloads/mysql-4.1.html.

- Subqueries and derived tables (unnamed views). See Section 13.1.8, « Sous-sélections (`SubSELECT`) ».

- `INSERT ... ON DUPLICATE KEY UPDATE ...` syntax. This allows you to `UPDATE` an existing row if the insert would cause a duplicate value in a `PRIMARY` or `UNIQUE` key. (`REPLACE` allows you to overwrite an existing row, which is something entirely different.) See Section 13.1.4, « Syntaxe de `INSERT` ».

- A newly designed `GROUP_CONCAT()` aggregate function. See Section 12.9, « Fonctions et options à utiliser dans les clauses `GROUP BY` ».

- Extensive Unicode (UTF8) support.

- Character sets can be defined per column, table, and database.

- New key cache for `MyISAM` tables with many tunable parameters. You can have multiple key caches, preload index into caches for batches...

- `BTREE` index on `HEAP` tables.

- Support for OpenGIS spatial types (geographical data). See Chapitre 18, Données spatiales avec MySQL.

- `SHOW WARNINGS` shows warnings for the last command. See Section 13.5.3.19, « `SHOW WARNINGS | ERRORS` ».

- Faster binary protocol with prepared statements and parameter binding. See Section 24.2.4, « Fonctions C de commandes préparées ».

- You can now issue multiple statements with a single C API call and then read the results in one go. See Section 24.2.9, « Gestion des commandes multiples avec l'interface C ».

- Create Table: `CREATE [TEMPORARY] TABLE [IF NOT EXISTS] table2 LIKE table1`.

- Server based `HELP` command that can be used in the `mysql` command line client (and other clients) to get help for SQL statements.

For a full list of changes, please refer to the changelog sections for each individual 4.1.x release.

### C.2.1. Changements de la version 4.1.12 (Pas encore publiée)

Fonctionnalités ajoutées ou modifiées :

- Updated version of `libedit` to 2.9. (Bug#2596)

- `InnoDB`: When `FOREIGN_KEY_CHECKS=0`, `ALTER TABLE` and `RENAME TABLE` will ignore any type incompatibilities between referencing and referenced columns. Thus, it will be possible to convert the character sets of columns that participate in a foreign key. Be sure to convert all tables before modifying any data! (Bug#9802)

- Previously in MySQL 4.1, an `Illegal mix of collations` error occurred when mixing strings from same character set when one had a non-binary collation and the other a binary collation. Now the binary collation takes precedence, so that both strings are treated as having the binary collation. This restores compatibility with MySQL 4.0 behavior.

Bogues corrigés :

- Security fix: If mysqld was started with `--user=`non_existent_user``, it would run using the privileges of the account it was invoked from, even if that was `root`. (Bug#9833)

- `MAX()` for an `INT UNSIGNED` (unsigned 4-byte integer) column could return negative values if the column contained values larger than 2^31. (Bug#9298)

- Fixed a deadlock resulting from use of `FLUSH TABLES WITH READ LOCK` while an `INSERT DELAYED` statement is in progress. (Bug#7823)

- Multiple-table updates could produce spurious data-truncation warnings if they used a join across columns that are indexed using a column prefix. (Bug#9103)

- Use of a subquery that used `WITH ROLLUP` in the `FROM` clause of the main query sometimes resulted in a `Column cannot be null` error. (Bug#9681)

- `RENAME TABLE` for an `ARCHIVE` table failed if the `.arn` file was not present. (Bug#9911)

- Fixed an optimizer problem where extraneous comparisons between `NULL` values in indexed columns were being done for operators such as `=` that are never true for `NULL`. (Bug#8877)

- `SELECT ROUND(`expr`)` produced a different result than `CREATE TABLE ... SELECT ROUND(`expr`)`. (Bug#9837)

- Fixed some awk script portability problems in cmd-line-utils/libedit/makelist.sh. (Bug#9954)

- Changed metadata for result of `SHOW KEYS`: Data type for `Sub_part` column now is `SMALLINT` rather than `TINYINT` because key part length can be longer than 255. (Bug#9439)

- Fixed some problems with myisampack on 64-bit systems that resulted in segmentation violations. (Bug#9487)

- Fixed an optimizer bug in computing the union of two ranges for the `OR` operator. (Bug#9348)

- Fixed an index corruption problem for `MyISAM` tables that resulted from the 4.1 behavior of padding values with blanks for comparison: Dumping a table with mysqldump, reloading it, and then re-running the binary log against it crashed the index and necessitated a repair. (Bug#9188)

- Fixed a segmentation fault in mysqlcheck that occurred when the last table checked in `--auto-repair` mode returned an error (such as the table being a `MERGE` table). (Bug#9492)

- Fixed the client/server protocol for prepared statements so that reconnection works properly when the connection is killed while reconnect is enabled. (Bug#8866)

- `INSERT ... ON DUPLICATE KEY UPDATE` incorrectly updated a `TIMESTAMP` column to the current timestamp, even if the update list included ``col_name` = `col_name`` for that column to prevent the update. (Bug#7806)

- Starting mysqld with the `--skip-innodb` and `--default-storage-engine=innodb` (or `--default-table-type=innodb` caused a server crash. (Bug#9815)

- Queries containing `CURRENT_USER()` incorrectly were registered in the query cache. (Bug#9796)

- A server installed as a Windows service and started with `--shared-memory` could not be stopped. (Bug#9665)

- mysqldump dumped core when invoked with `--tmp` and `--single-transaction` options and a non-existent table name. (Bug#9175)

- Additional fix for `mysql_server_init()` and `mysql_server_end()` C API functions so that stopping and restarting the embedded server will not cause a crash. (Bug#7344)

- mysql.server no longer uses non-portable alias command or LSB functions. (Bug#9852)

- Fixed a `readline`-related crash in mysql when the user pressed Control-R. (Bug#9568)

- `TIMEDIFF()` with a negative time first argument and postive time second argument produced incorrect results. (Bug#8068)

- Fixed a bug that caused concurrent inserts to be allowed into the tables in the `SELECT ... UNION ...` part of `INSERT ... SELECT ... UNION ...`. This could result in the incorrect order of queries in the binary log. (Bug#9922)

- Warning message from `GROUP_CONCAT()` did not always indicate correct number of lines. (Bug#8681)

- InnoDB: `ENUM` and `SET` columns were treated incorrectly as character strings. This bug did not manifest itself with `latin1` collations, but it caused malfunction with `utf8`. Old tables will continue to work. In new tables, `ENUM` and `SET` will be internally stored as unsigned integers. (Bug#9526)

- InnoDB: Avoid test suite failures caused by a locking conflict between two server instances at server shutdown/startup. This conflict on advisory locks appears to be the result of a bug in the operating system; these locks should be released when the files are closed, but somehow that does not always happen immediately in Linux. (Bug#9381)

- `InnoDB`: Prevent `ALTER TABLE` from changing the storage engine if there are foreign key constraints on the table. (Bug#5574, Bug#5670)

- `InnoDB`: Fixed a deadlock without any locking, simple select and update. (Bug#7975) `InnoDB` now takes an exclusive lock when `INSERT ON DUPLICATE KEY UPDATE` is checking duplicate keys.

### C.2.2. Changements de la version 4.1.11 (1 avril 2005)

Fonctionnalités ajoutées ou modifiées :

- `ONLY_FULL_GROUP_BY` no longer is included in the `ANSI` composite SQL mode. (Bug#8510)

- mysqld_safe will create the directory where the UNIX socket file is to be located if the directory does not exist. This applies only to the last component of the directory pathname. (Bug#8513)

- The coercibility for the return value of functions such as `USER()` or `VERSION()` now is ``system constant'' rather than ``implicit.'' This makes these functions more coercible than column values so that comparisons of the two do not result in `Illegal mix of collations` errors. `COERCIBILITY()` was modified to accommodate this new coercibility value. See Section 12.8.3, « Fonctions d'informations ».

- User variable coercibility has been changed from ``coercible'' to ``implicit.'' That is, user variables have the same coercibility as column values.

- `NULL` now is considered more coercible than string constants. This resolves some `Illegal mix of collations` conflicts.

- Modified the parser to allow `SELECT` statements following the `UNION` keyword to be subqueries in parentheses. (Bug#2435)

- For slave replication servers started with `--replicate-*` options, statements that should not be replicated according those options no longer are written to the slave's general query log. (Bug#8297)

- Added `SQL_NOTES` session variable to cause `Note`-level warnings not to be recorded. (Bug#6662)

- `InnoDB`: Commit after every 10,000 copied rows when executing `CREATE INDEX`, `DROP INDEX` or `OPTIMIZE TABLE`, which are internally implemented as `ALTER TABLE`. This makes it much faster to recover from an aborted operation.

- Added a new global system variable `slave_transaction_retries`: If the replication slave SQL thread fails to execute a transaction because of an `InnoDB` deadlock or exceeded InnoDB's `innodb_lock_wait_timeout` or NDBCluster's `TransactionDeadlockDetectionTimeout` or `TransactionInactiveTimeout`, it automatically retries `slave_transaction_retries` times before stopping with an error. The default in MySQL 4.1 is 0. You must explicitly set the value greater than 0 to enable the ``retry'' behavior. (In MySQL 5.0.3 or newer, the default is 10.) (Bug#8325)

- Added `--with-big-tables` compilation option to configure. (Previously it was necessary to pass `-DBIG_TABLES` to the compiler manually in order to enable large table support.) See Section 2.4.2, « Options habituelles de `configure` » for details.

- Added configuration directives `!include` and `!includedir` for including option files and searching directories for option files. See Section 4.3.2, « Fichier d'options `my.cnf` » for usage.

Bogues corrigés :

- The use of `XOR` together with `NOT ISNULL()` erroneously resulted in some outer joins being converted to inner joins by the optimizer. (Bug#9017)

- Fixed `utf8_spanish2_ci` and `ucs2_spanish2_ci` collations to not consider ‘`r`’ equal to ‘`rr`’. If you upgrade to this version from an earlier version, you should rebuild the indexes of affected tables. (Bug#9269)

- Allow extra HKSCS and cp950 characters (`big5` extension characters) to be accepted in `big5` columns. (Bug#9357)

- `BLOB(`M`)` and `TEXT(`M`)` columns, with `M` less than 256, were being created as `BLOB` and `TEXT` columns rather than `TINYBLOB` or `TINYTEXT` columns. (Bug#9303)

- Fixed a problem with `INSERT ... SELECT ... ON DUPLICATE KEY UPDATE` where a column named in the insert list and in the `ON DUPLICATE KEY UPDATE` clause was erroneously declared to be ambiguous. (Bug#8147)

- In prepared statements, subqueries containing parameters were erroneously treated as `const` tables during preparation, resulting in a server crash. (Bug#8807)

- Fixed a problem with `OPTIMIZE TABLE` for `InnoDB` tables being written twice to the binary log. (Bug#9149)

- Provide more informative error messages in clustered setting when a query is issued against a table that has been modified by another `mysqld` server. (Bug#6762)

- For `MyISAM` tables, `REPAIR TABLE` no longer discard rows that have incorrect checksum. (Bug#9824)

- Depending on index statistics, `GROUP BY `col1`, `col2`, ...` could return incorrect results if the first table processed for a join had several indexes that cover the grouped columns. (Bug#9213)

- Fixed incorrect evaluation of `ALL/ANY` subqueries that contain a `HAVING` clause. (Bug#9350)

- Fixed server crash when left expression of `IN/ALL/ANY` comparision was a subquery. (Bug#8888)

- Fixed option-parsing code for the embedded server to understand `K`, `M`, and `G` suffixes for the `net_buffer_length` and `max_allowed_packet` options. (Bug#9472)

- Fixed a crash when using `TIMESTAMP` columns with no minute or second parts in `GROUP BY` with the `new` system variable set to 1. (Bug#9401)

- If a `MyISAM` table on Windows had `INDEX DIRECTORY` or `DATA DIRECTORY` table options, mysqldump dumped the directory pathnames with single-backslash pathname separators. This would cause syntax errors when importing the dump file. mysqldump now changes ‘`\`’ to ‘`/`’ in the pathnames on Windows. (Bug#6660)

- Fixed a server crash caused by use of `NOW()` is a subquery. (Bug#8824)

- Fixed problems with static variables to allow building on Fedora Core 3. (Bug#6554)

- Some user variables were not being handled with ``implicit'' coercibility. (Bug#9425)

- Setting the `max_error_count` system variable to 0 resulted in a setting of 1. (Bug#9072)

- Fixed a collation coercibility problem that caused a union between binary and non-binary columns to fail. (Bug#6519)

- Fixed a problem with the `tee` command in mysql that resulted in mysql crashing. (Bug#8499)

- On Windows, create shared memory objects with the proper access rights to make them usable when the client and server are running under different accounts. (Bug#8226)

- Bundled `zlib` in the source distribution was upgraded to 1.2.2. (Bug#9118)

- Fixed server crash resulting from queries that combined `SELECT DISTINCT`, `SUM()`, and `ROLLUP`. (Bug#8615)

- Incorrect results were returned from queries that combined `SELECT DISTINCT`, `GROUP BY` , and `ROLLUP`. (Bug#8616)

- Fixed a bug that under certain circumstances could allow a privilege escalation via database wildcards in `GRANT`. (CAN-2004-0957)

- Too many rows were returned from queries that combined `ROLLUP` and `LIMIT` if `SQL_CALC_FOUND_ROWS` was given. (Bug#8617)

- mysqldump misinterpreted ‘`_`’ and ‘`%`’ characters in the names of tables to be dumped as wildcard characters. (Bug#9123)

- Made the `relay_log_space_limit` system variable show up in the output of `SHOW VARIABLES`. (Bug#7100)

- Use of `GROUP_CONCAT(`x`)` in a subquery, where `x` was an alias to a column in the outer query, resulted in a server crash. (Bug#8656)

- The `CHARSET()`, `COLLATION()`, and `COERCIBILITY()` functions sometimes returned `NULL`. `CHARSET()` and `COLLATION()` returned `NULL` when given any of these arguments that evaluated to `NULL`: A system function such as `DATABASE()`; a column value; and a user variable. Now `CHARSET()` and `COLLATION()` return the system character set and collation; the column character set and collation; and `binary`. `COERCIBILITY(NULL)` now returns ``ignorable'' coercibility rather than `NULL`. (Bug#9129)

- Expressions involving nested `CONCAT()` calls and character set conversion of string constants could return an incorrect result. (Bug#8785)

- The `MEMORY` storage engine did not properly increment an `AUTO_INCREMENT` column if there was a second composite index that included the column. (Bug#8489)

- Fixed a bug in the filesort routine such that killing a filesort could cause an assertion failure. (Bug#8799)

- `REPAIR TABLE` did not invalidate query results in the query cache that were generated from the table. (Bug#8480)

- If `max_join_size` was set, a query containing a subquery that exceeded the examined-rows limit could hang. (Bug#8726)

- Mixed-case database and table names in the grant tables were ignored for authentication if the `lower_case_table_names` system variable was set. `GRANT` will not create such privileges when `lower_case_table_names` is set, but it is possible to create them by direct manipulation of the grant tables, or that old grant records were present before setting the variable. (Bug#7989)

- `AES_DECRYPT(`col_name`,`key`)` could fail to return `NULL` for invalid values in `col_name`, if `col_name` was declared as `NOT NULL`. (Bug#8669)

- Ordering by unsigned expression (more complex than a column reference) was treating the value as signed, producing incorrectly sorted results. (Bug#7425)

- `HAVING` was treating unsigned columns as signed. (Bug#7425)

- Fixed a problem with boolean full-text searches on `utf8` columns where a double quote in the search string caused a server crash. (Bug#8351)

- `MIN(`col_name`)` and `MAX(`col_name`)` could fail to produce the correct result if `col_name` was contained in multiple indexes and the optimizer did not choose the first index that contained the column. (Bug#8893)

- Table creation for a `MyISAM` table failed if `DATA DIRECTORY` or `INDEX DIRECTORY` options were given that specified the pathname to the database directory where the table files would be created by default. (Bug#8707)

- Fixed a problem with `LIKE` pattern-matching for strings with the `cp1251_bin` binary collation. (Bug#8560)

- A join on two tables failed when each contained a `BIGINT UNSIGNED` column that were compared when their values exceeded 2^63 − 1. The match failed and the join returned no rows. (Bug#8562)

- For a query with both `GROUP BY` and `COUNT(DISTINCT)` clauses and a `FROM` clause with a subquery, `NULL` was returned for any `VARCHAR` column selected by the subquery. (Bug#8218)

- Fixed an optimizer bug that caused incorrectly ordered result from a query that used a `FULLTEXT` index to retrieve rows and there was another index that was usable for `ORDER BY`. For such a query, `EXPLAIN` showed `fulltext` join type, but regular (not `FULLTEXT`) index in the `Key` column. (Bug#6635)

- For a statement string that contained multiple slow queries, only the last one would be written to the slow query log. (Bug#8475)

- When the server was started with `--skip-name-resolve`, specifying hostname values that included netmasks in `GRANT` statements did not work. (Bug#8471)

- The `--set-character-set` option for myisamchk was changed to `--set-collation`. The value needed for specifying how to sort indexes is a collation name, not a character set name. (Bug#8349)

- Hostname matching didn't work if a netmask was specified for table-specific privileges. (Bug#3309)

- Binary data stored in `BLOB` or `BINARY` columns would be erroneously dumped if mysqldump was invoked with `--hex-blob` and `--skip-extended-insert` arguments. This happened if data contained characters larger then 0x7F (Bug#8830).

- Corruption of `MyISAM` table indexes could occur with `TRUNCATE TABLE` if the table had already been opened. For example, this was possible if the table had been opened implicitly by selecting from a `MERGE` table that mapped to the `MyISAM` table. The server now issues an error message for `TRUNCATE TABLE` under these conditions. (Bug#8306)

- Fixed handling of table-name matching in mysqlhotcopy to accommodate `DBD::mysql` 2.9003 and up (which implement identifier quoting). (Bug#8136)

- In the `mysql_real_escape_string()` C API function, when a multi-byte character is encountered that is illegal in the current character set, escape only the first byte, not each byte. This avoids creating a valid character from an invalid one. (Bug#8378)

- Fixed a problem with the `cp1250_czech_cs` collation that caused empty literal strings not to compare equal to empty character columns. (Bug#8840)

- Fixed a problem in index cost calculation that caused a `USE INDEX` or `FORCE INDEX` hint not to be used properly for a `LEFT JOIN` across indexed `BLOB` columns. (Bug#7520)

- The column type for `MAX(`datetime_col`)` was returned as `VARCHAR` rather than `DATETIME` if the query included a `GROUP BY` clause. (Bug#5615)

- `FOUND_ROWS()` returned an incorrect value for preceding `SELECT` statements that used no table or view. (Bug#6089)

- In string literals with an escape character (‘`\`’) followed by a multi-byte character that has a second byte of ‘`\`’, the literal was not interpreted correctly. The next character now is escaped, not just the next byte. (Bug#8303)

- InnoDB: Work around a problem in AIX 5.1 patched with ML7 security patch: InnoDB would refuse to open its `ibdata` files, complaining about an operating system error 0.

- InnoDB: Fixed a memory corruption bug if one created a table with a primary key that contained at least two column prefixes. An example: `CREATE TABLE t(a char(100), b tinyblob, PRIMARY KEY(a(5), b(10)))`.

- `InnoDB`: Do not try to space-pad `BLOB` columns containing `ucs2` characters. This avoids an assertion failure that was introduced when fixing Bug#7350. (Bug#8771)

- InnoDB: Fixed a bug : MySQL-4.1.8 - 4.1.10 could complain that an InnoDB table created with MySQL-3.23.49 or earlier was in the new compact InnoDB table format of 5.0.3 or later, and InnoDB would refuse to use that table. There is nothing wrong with the table, it is mysqld that is in error. Workaround: wait that 4.1.11 is released before doing an upgrade, or dump the table and recreate it with any MySQL version >= 3.23.50 before upgrading.

- `InnoDB`: Honor the `--tmpdir` startup option when creating temporary files. Previously, `InnoDB` temporary files were always created in the temporary directory of the operating system. On Netware, `InnoDB` will continue to ignore `--tmpdir`. (Bug#5822)

- `InnoDB`: If MySQL wrote to its binlog, but for some reason `trx->update_undo` and `trx->insert_undo` were NULL in InnoDB, then `trx->commit_lsn` was garbage, and InnoDB could assert in the log flush of `trx_commit_complete_for_mysql()`. (Bug#9277)

- `InnoDB`: If InnoDB cannot allocate memory, keep retrying for 60 seconds before we intentionally crash `mysqld`; maybe the memory shortage is just temporary.

- `InnoDB`: If one used `LOCK TABLES`, created an InnoDB temp table, and did a multi-table update where a MyISAM table was the update table and the temp table was a read table, then InnoDB asserted in `row0sel.c` because `n_mysql_tables_in_use` was 0. Also, we remove the assertion altogether and just print an error to the `.err` log if this important consistency check fails. (Bug#8677)

- mysqldump now avoids writing `SET NAMES` to the dump output if the server is older than version 4.1 and would not understand that statement. (Bug#7997)

- Fixed a bug in my_print_defaults that made it ignore the `--defaults-extra-file` and `--defaults-file` options.

- Retrieving from a view defined as a `SELECT` that mixed `UNION ALL` and `UNION DISTINCT` resulted in a different result than retrieving from the original `SELECT`. (Bug#6565)

- Worked around a bug in support for NSS support in `glibc` when static linking is used and LDAP is one of the NSS sources. The workaround is to detect when the bug causes a segfault and issue a diagnostic message with information about the problem. (Bug#3037, Bug#4872)

- If the mysql prompt was configured to display the default database name, and that database was dropped, mysql did not update the prompt. (Bug#4802)

- perror was printing a spurious extra line of output ("Error code ###: Unknown error ###" printed directly before the correct line with the error message). (Bug#8517)

- The `CHAR()` function was not ignoring `NULL` arguments, contrary to the documentation. (Bug#6317)

- Neither `SHOW ERRORS` nor `SHOW WARNINGS` were displaying Error-level messages. (Bug#6572)

- Creating a table using a name containing a character that is illegal in `character_set_client` resulted in the character being stripped from the name and no error. The character now is considered an error. (Bug#8041)

- Fixed a problem with the Cyrillic letters I and SHORT I being treated the same by the `utf8_general_ci` collation. (Bug#8385)

- The `MAX_CONNECTIONS_PER_HOUR` resource limit was not being reset hourly and thus imposed an absolute limit on number of connections per account until the server is restarted or the limits flushed. (Bug#8350)

- With a database was dropped with `lower_case_table_names=2`, tables in the database also were dropped but not being flushed properly from the table cache. If the database was recreated, the tables also would appear to have been recreated. (Bug#8355)

- Changed `mysql_server_end()` C API function to restore more variables to their initial state so that a subsequent call to `mysql_server_init()` would not cause a client program crash. (Bug#7344)

- Fixed a problem with accented letters improperly being treated as distinct with the `utf_general_ci` collation. (Bug#7878)

- `ENUM` and `SET` columns in privilege tables incorrectly had a case-sensitive collation, resulting in failure of assignments of values that did not have the same lettercase as given in the column definitions. The collation was changed to be case insensitive. (Bug#7617)

- An expression that tested a case-insensitive character column against string constants that differed in lettercase could fail because the constants were treated as having a binary collation. (For example, `WHERE city='London' AND city='london'` could fail.) (Bug#7098, Bug#8690)

- The output of the `STATUS` (`\s`) command in mysql had the values for the server and client character sets reversed. (Bug#7571)

- If the slave was running with `--replicate-*-table` options which excluded one temporary table and included another, and the two tables were used in a single `DROP TEMPORARY TABLE IF EXISTS` statement, as the ones the master automatically writes to its binary log upon client's disconnection when client has not explicitly dropped these, the slave could forget to delete the included replicated temporary table. Only the slave needs to be upgraded. (Bug#8055)

- Treat user variables as having `IMPLICIT` derivation (coercibility) to avoid ``Illegal mix of collations'' errors when replicating user variables. (Bug#6676)

- When setting integer system variables to a negative value with `SET VARIABLES`, the value was treated as a positive value modulo 2^32. (Bug#6958)

- Fixed a bug in bundled `readline` library that caused segmentation fault in mysql when user entered Shift+Enter. (Bug#5672)

- Fix conversion of strings -> double to get higher accuracy for floating point values that are integers, like: `123.45E+02` (Bug#7840).

- Fixed a bug in `MATCH ... AGAINST` in natural language mode that could cause a server crash if the `FULLTEXT` index was not used in a join (`EXPLAIN` did not show `fulltext` join mode) and the search query matched no rows in the table (Bug#8522).

- Platform and architecture information in version information produced for `--version` option on Windows was always `Win95/Win98 (i32)`. More accurately determine platform as `Win32` or `Win64` for 32-bit or 64-bit Windows, and architecture as `ia32` for x86, `ia64` for Itanium, and `axp` for Alpha. (Bug#4445)

- Fixed a rare race condition which could lead to `FLUSH TABLES WITH READ LOCK` hanging. (Bug#8682)

- Fixed a bug that caused the slave to stop on statements that produced an error on the master. (Bug#8412)

- If multiple semicolon-separated statements were received in a single packet, they were written to the binary log as a single event rather than as separate per-statement events. For a server serving as a replication master, this caused replication to fail when the event was sent to slave servers. (Bug#8436)

### C.2.3. Changements de la version 4.1.10 (12 février 2005)

Note: The security improvements related to creation of table files and to user-defined functions were made after MySQL 4.1.10 was released and are present in MySQL 4.1.10a. We would like to thank Stefano Di Paola `<stefano.dipaola@wisec.it>` for making us aware of these.

Fonctionnalités ajoutées ou modifiées :

- Added back faster subquery execution from 4.1.8. This adds also back a bug from 4.1.8 in comparing `NULL` to the value of a subquery. See Section 1.5.7.4, « Bugs connus / limitations de MySQL ».

- Security improvement: The server creates `.frm`, `.MYD`, `.MYI`, `.MRG`, `.ISD`, and `.ISM` table files only if a file with the same name does not already exist. Thanks to Stefano Di Paola `<stefano.dipaola@wisec.it>` for finding and informing us about this issue. (CAN-2005-0711)

- Security improvement: User-defined functions should have at least one symbol defined in addition to the `xxx` symbol that corresponds to the main `xxx()` function. These auxiliary symbols correspond to the `xxx_init()`, `xxx_deinit()`, `xxx_reset()`, `xxx_clear()`, and `xxx_add()` functions. mysqld by default no longer loads UDFs unless they have at least one auxiliary symbol defined in addition to the main symbol. The `--allow-suspicious-udfs` option controls whether UDFs that have only an `xxx` symbol can be loaded. By default, the option is off. `mysqld` also checks UDF filenames when it reads them from the `mysql.func` table and rejects those that contain directory pathname separator characters. (It already checked names as given in `CREATE FUNCTION` statements.) See Section 27.2.3.1, « Fonctions utilisateur : appeler des fonctions simples », Section 27.2.3.2, « Appeler des fonctions utilisateurs pour les groupements », and Section 27.2.3.6, « Précautions à prendre avec les fonctions utilisateur ». Thanks to Stefano Di Paola `<stefano.dipaola@wisec.it>` for finding and informing us about this issue. (CAN-2005-0709, CAN-2005-0710)

- Setting the connection collation to a value different from the server collation followed by a `CREATE TABLE` statement that included a quoted default value resulted in a server crash. (Bug#8235)

- Thread stack size was increased from 192KB to 256KB on Linux/IA-64 (too small stack size was causing server crashes on some queries). (Bug#8391)

- From the Windows distribution, predefined accounts without passwords for remote users ("root@%", "@%") were removed (other distributions never had them).

- Added `mysql_library_init()` and `mysql_library_end()` as synonyms for the `mysql_server_init()` and `mysql_server_end()` C API functions. `mysql_library_init()` and `mysql_library_end()` are `#define` symbols, but the names more clearly indicate that they should be called when beginning and ending use of a MySQL C API library no matter whether the application uses `libmysqlclient` or `libmysqld`. (Bug#6149)

- The server now issues a warning when `lower_case_table_names=2` and the data directory is on a case-sensitive filesystem, just as when `lower_case_table_names=0` on a case-insensitive filesystem. (Bug#7887)

- The server now issues a warning to the error log when it encounters older tables that contain character columns that might be interpreted by newer servers to have a different column length. (Bug#6913) See Section 2.6.2, « Passer de la version 4.0 à la version 4.1 » for a discussion of this problem and what to do about it.

- InnoDB: When MySQL/InnoDB is compiled on Mac OS X 10.2 or earlier, detect the operating system version at run time and use the `fcntl()` file flush method on Mac OS X versions 10.3 and later. Apple had disabled `fsync()` in Mac OS X for internal disk drives, which caused corruption at power outages.

- InnoDB: A shared record lock (`LOCK_REC_NOT_GAP`) is now taken for a matching record in the foreign key check because inserts can be allowed into gaps.

- InnoDB: Relaxed locking in INSERT...SELECT, single table UPDATE...SELECT and single table DELETE...SELECT clauses when innobase_locks_unsafe_for_binlog is used and isolation level of the transaction is not serializable. `InnoDB` uses consistent read in these cases for a selected table.

Bogues corrigés :

- `FOUND_ROWS()` returned an incorrect value after a `SELECT SQL_CALC_FOUND_ROWS DISTINCT` statement that selected constants and included `GROUP BY` and `LIMIT` clauses. (Bug#7945)

- Fixed a bug in cardinality estimations for `HASH` indexes of `TEMPORARY` tables created using `MEMORY` storage engine. As a result queries that were using this index (as shown by `EXPLAIN`) could have returned incorrect results. (Bug#8371)

- Corrected a problem with references to `DUAL` where statements such as `SELECT 1 AS a FROM DUAL` would succeed but statements such as `SELECT 1 AS a FROM DUAL LIMIT 1` would fail. (Bug#8023)

- Fixed a server crash caused by `DELETE FROM `tbl_name` ... WHERE ... ORDER BY `tbl_name`.`col_name`` when the `ORDER BY` column was qualified with the table name. (Bug#8392)

- mysqld had problems finding its language files if the `basedir` value was specified as a very long pathname. (Bug#8015)

- Updates were being written to the binary log when there were `binlog-do-db` or `binlog-ignore-db` options even when there was no current database, contrary to Section 5.9.4, « Le log binaire ». (Bug#6749)

- Fixed conversion of floating-point values to character fields when the absolute value of the float was less than 1, and also fixed calculation of length for negative values. (Bug#7774)

- Column headers in query results retrieved from the query cache could be corrupted when a non-4.1 client was served a result originally generated for a 4.1 client. The query cache was not keeping track of which client/server protocol was being used. (Bug#6511)

- Fixed `LOAD INDEX` statement to actually load index in memory. (Bug#8452)

- If multiple prepared statements were executed without retrieving their results, executing one of them again would cause the client program to crash. (Bug#8330)

- Non-numeric values inserted into a `YEAR` column were being stored as `2000` rather than as `0000`. (Bug#6067)

- Fixed a failure of multiple-table updates to replicate properly on slave servers when `--replicate-*-table` options had been specified. (Bug#7011)

- `mysql_stmt_close()` C API function was not clearing an error indicator when a previous prepare call failed, causing subsequent invocations of error-retrieving calls to indicate spurious error values. (Bug#7990)

- Fixed failure of `CREATE TABLE ... LIKE` Windows when the source or destination table was located in a symlinked database directory. (Bug#6607)

- With `lower_case_table_names` set to 1, mysqldump on Windows could write the same table name in different lettercase for different SQL statements. Fixed so that consistent lettercase is used. (Bug#5185) `HAVING` that referred to `RAND()` or a user-defined function in the `SELECT` part through an alias could cause a crash or wrong value. (Bug#8216)

- If one used `CONVERT_TZ()` function in `SELECT`, which in its turn was used in `CREATE TABLE` statements, then system time zone tables were added to list of tables joined in SELECT and thus erroneous result was produced. (Bug#7899)

- Fixed a bug in `CONV()` function returning unsigned `BIGINT` number (third argument is positive, and return value does not fit in 32 bits). (Bug#7751)

- Fixed a failure of the `IN()` operator to return correct result if all values in the list were constants and some of them were using substring functions, for example, `LEFT()`, `RIGHT()`, or `MID()`.

- Fixed problem with `SHOW INDEX` reporting `Sub_part` values in bytes rather than characters for columns with a multi-byte character set. (Bug#7943)

- Fixed a crash in `CONVERT_TZ()` function when its second or third argument was from a `const` table (see Section 7.2.1, « Syntaxe de `EXPLAIN` (Obtenir des informations sur les `SELECT`) »). (Bug#7705)

- Correct a problem with mysql_config, which was failing to produce proper `zlib` option for linking under some circumstances. (Bug#6273)

- Fixed a problem with calculation of number of columns in row comparison against a subquery. (Bug#8020)

- Fixed erroneous output resulting from `SELECT DISTINCT` combined with a subquery and `GROUP BY`. (Bug#7946)

- Fixed server crash in comparing a nested row expression (for example `row(1,(2,3))`) with a subquery. (Bug#8022)

- Fixed server crash resulting from certain correlated subqueries with forward references (referring to an alias defined later in the outer query). (Bug#8025)

- Fixed server crash resulting from re-execution of prepared statements containing subqueries. (Bug#8125)

- Removed a dependence of boolean full-text search on `--default-character-set` option. (Bug#8159)

- Fixed a crash in a boolean full-text search in certain joins. (Bug#8234)

- Fixed erroneous comparison where strings that began with `CHAR(31)` were considered equal to the empty string. (Bug#8134)

- Add description of `debug` command to mysqladmin help output. (Bug#8207)

- perror.exe was always returning ``Unknown error'' on Windows. See Section 8.12, « `perror`, expliquer les codes d'erreurs ». (Bug#7390)

- Modify `SET` statements produced by mysqldump to write quoted strings using single quotes rather than double quotes. This avoids problems if the dump file is reloaded while the `ANSI_QUOTES` SQL mode is in effect. (Bug#8148)

- Fixed a bug where `ALTER TABLE` improperly would accept an index on a `TIMESTAMP` column that `CREATE TABLE` would reject. (Bug#7884)

- Fixed a bug in multiple-table `UPDATE` statements that could cause spurious `Table '#sql_....' is full` errors if the number of rows to update is big enough. (Bug#7788)

- Fixed a problem where `SHOW INDEX` on a `MERGE` table could crash a debugging version of the server. (Bug#7377)

- Fixed a problem where adding an `ORDER BY` clause for an indexed column would cause a `SELECT` to return an empty result. (Bug#7331)

- Fixed a problem where `ALTER TABLE` on a `TEMPORARY` table with a mixed-lettercase name could cause the table to disappear when `lower_case_table_names` was set to 2. (Bug#7261)

- Fixed a problem with key cache statistics being reported incorrectly by the server after receipt of a `SIGHUP` signal. (Bug#4285)

- Fixed a problem that caused `mysql_stmt_prepare()` to be very slow when used in client programs on Windows. (Bug#5787)

- For indexes, `SHOW CREATE TABLE` now displays the index type even if it is the default, for storage engines that support multiple index types. (Bug#7235)

- Fixed a bug where the use of `GROUP_CONCAT()` with `HAVING` caused a server crash. (Bug#7769)

- Fixed a bug where comparing the result of a subquery to a non-existent column caused a server crash on Windows. (Bug#7885)

- Fixed a bug which caused `TIMEDIFF()` function to return wrong results if one of its arguments had non-zero microsecond part (Bug#7586).

- Fixed a bug which caused `TIMESTAMP` columns with display width specified to be not identical to `DATETIME` columns when server was run in `MAXDB` mode (Bug#7418).

- Fixed a bug in `UNION` statements that resulted in the wrong number of the examined rows reported in the slow query log.

- Fixed a bug in a combination of `-not` and `trunc*` operators of full-text search. Using more than one truncated negative search term, was causing empty result set.

- InnoDB: Fixed a bug introduced in 4.1.9 to the Windows version if you used `innodb_file_per_table`. mysqld would stop and complain about Windows error number 87 in a file operation. (See the Bugs database or the 4.1.9 change notes about a workaround for that bug in 4.1.9). (Bug#8021)

- InnoDB: Corrected the handling of trailing spaces in the `ucs2` character set. (Bug#7350)

- InnoDB: Use native `tmpfile()` function on Netware. All InnoDB temporary files are created under `sys:\tmp`. Previously, InnoDB temporary files were never deleted on Netware.

- InnoDB: Fix a race condition that could cause the assertion `space->n_pending_flushes == 0` to fail in `fil0fil.c`, in `fil_space_free()`, in `DROP TABLE` or in `ALTER TABLE`.

- InnoDB: `ALTER TABLE ... ADD CONSTRAINT PRIMARY KEY ...` complained about bad foreign key definition. (Bug#7831)

- InnoDB: Fix a theoretical hang over the adaptive hash latch in InnoDB if one runs `INSERT ... SELECT ...` (binlog not enabled), or a multi-table `UPDATE` or `DELETE`, and only the read tables are InnoDB type, the rest are MyISAM. (Bug#7879)

- Fixed a bug in `max_heap_table_size` handling, that resulted in `Table is full` error when the table was still smaller than the limit. (Bug#7791).

- Fixed a symlink vulnerability in the mysqlaccess script. Reported by Javier Fernandez-Sanguino Pena and Debian Security Audit Team. (CAN-2005-0004)

- mysqlbinlog forgot to add backquotes around the collation of user variables (causing later parsing problems as `BINARY` is a reserved word). (Bug#7793)

- Ensured that mysqldump --single-transaction sets its transaction isolation level to `REPEATABLE READ` before proceeding (otherwise if the MySQL server was configured to run with a default isolation level lower than `REPEATABLE READ` it could give an inconsistent dump). (Bug#7850)

- Changed mysql client so that including `\p` as part of a prompt command uses the name of the shared memory connection when the connection is using shared memory. (Bug#7922)

- Fixed a problem in the server where executing a multi-statement query more than once with the query cache active could yield incorrect result sets. (Bug#7966)

- Fixed that a 4.1.10 slave can connect to a master < 3.23.50 without hanging (the reason for the hang is a bug in these quite old masters -- `SELECT @@unknown_var` hangs them -- which was fixed in MySQL 3.23.50). (Bug#7965)

- Fixed a bug where MySQL was allowing concurrent updates (inserts, deletes) to a table if binary logging is enabled. Changed to ensure that all updates are executed in a serialized fashion, because they are executed serialized when binlog is replayed. (Bug#7879)

### C.2.4. Changements de la version 4.1.9 (11 Janvier 2005)

Fonctionnalités ajoutées ou modifiées :

- mysqld_safe no longer tests for the presence of the data directory when using a relatively located server binary. It just assumes the directory is there, and fails to start up if it is not. This allows the data directory location to be specified on the command line, and avoids running a server binary that was not intended. (Bug#7249)

- The naming scheme of the Windows installation packages has changed slightly:

  - The platform suffix was changed from `-win` to `-win32`

  - The product descriptions `-noinstall` and `-essential` have been moved in front of the version number

  Examples: `mysql-essential-4.1.9-win32.msi`, `mysql-noinstall-4.1.9-win32.zip` See Section 2.2.1, « Installer MySQL sous Windows ».

- The Mac OS X 10.3 installation disk images now include a MySQL Preference Pane for the Mac OS X Control Panel that enables the user to start and stop the MySQL server via the GUI and activate and deactivate the automatic MySQL server startup on bootup.

- The `MySQL-shared-compat` Linux RPM now includes the 3.23 as well as the 4.0 `libysqlclient.so` shared libraries. (Bug#6342)

- `Seconds_Behind_Master` is `NULL` (which means ``unknown'') if the slave SQL thread is not running, or if the slave I/O thread is not running or not connected to master. It is zero if the SQL thread has caught up with the I/O thread. It no longer grows indefinitely if the master is idle.

- InnoDB: Do not acquire an internal `InnoDB` table lock in `LOCK TABLES` if `AUTOCOMMIT=1`. This helps in porting old `MyISAM` applications to `InnoDB`. `InnoDB` table locks in that case caused deadlocks very easily.

- InnoDB: Print a more descriptive error and refuse to start `InnoDB` if the size of `ibdata` files is smaller than what is stored in the tablespace header; `innodb_force_recovery` overrides this.

- The MySQL server aborts immediately instead of simply issuing a warning if it is started with the `--log-bin` option but cannot initialize the binary log at startup (that is, an error occurs when writing to the binary log file or binary log index file).

- The binary log file and binary log index file now behave like `MyISAM` when there is a "disk full" or "quota exceeded" error. See Section A.4.3, « Comment MySQL gère un disque plein ».

Bogues corrigés :

- Fixed problem where running mysql_fix_privilege_tables could result in grant table columns with too-short lengths if the server character set had been set to a multi-byte character set first. (Bug#7539)

- InnoDB: Fixed the critical bug if you enabled `innodb_file_per_table` in `my.cnf`. If you shut down mysqld, records could disappear from the secondary indexes of a table. Unfortunately, on Windows a new Bug#8021 was introduced. Windows users of `innodb_file_per_table` should put a line `innodb_flush_method=unbuffered` to their `my.cnf` or `my.ini` to work around 8021. (Bug#7496)

- InnoDB: Fixed a bug : 32-bit mysqld binaries built on HP-UX-11 did not work with `InnoDB` files greater than 2 GB in size. (Bug#6189)

- InnoDB: Return a sensible error code from `DISCARD TABLESPACE` if it fails because the table is referenced by a `FOREIGN KEY`.

- InnoDB: Fixed a bug : `InnoDB` failed to drop a table in the background drop queue if the table was referenced by a `FOREIGN KEY` constraint.

- InnoDB: Fixed a bug : if we dropped a table where an `INSERT` was waiting for a lock to check a `FOREIGN KEY` constraint, then an assertion would fail in `lock_reset_all_on_table()`.

- InnoDB: Fix a little bug: we looked at the physical size of a stored SQL `NULL` value from a wrong field in the index; this has probably caused no bugs visible to the user. It caused only some extra space to be used in some rare cases.

- InnoDB: Use the `fcntl()` file flush method on Mac OS X versions 10.3 and up. Apple had disabled `fsync()` in Mac OS X for internal disk drives, which caused corruption at power outages.

- mysqladmin password now checks whether the server has `--old-passwords` turned on or predates 4.1 and uses the old-format password if so. (Bug#7451)

- Added a `--default-character-set` option to mysqladmin to avoid problems when the default character set is not `latin1`. (Bug#7524)

- Fix a problem with truncation of `FLOAT` values. (Bug#7361)

- Fixed a bug in `PROCEDURE ANALYSE()`, which did not quote some `ENUM` values properly. (Bug#2813)

- Fixed a bug that caused incorrect results for complex datetime expressions containing casts of datetime values to `TIME` or `DATE` values. (Bug#6914)

- Include compression library flags in the output from mysql_config --lib_r. (Bug#7021)

- Corrected a problem with mysql_config not producing all relevant flags from `CFLAGS`. (Bug#6964)

- Corrected a problem with mysqld_safe not properly capturing output from ps. (Bug#5878)

- Fixed a bug that caused a linking failure when linking both the MySQL client library and IMAP library. (Bug#7428)

- Fixed table corruption bug when using `INSERT DELAYED` with prepared statements.

- Fixed a bug that caused microseconds to be gobbled from the string result of the `STR_TO_DATE` function, if there is some other specifier in the format string following `%f`. (Bug#7458)

- Made the MySQL server accept executing `SHOW CREATE DATABASE` even if the connection has an open transaction or locked tables. Refusing it made mysqldump --single-transaction sometimes fail to print a complete `CREATE DATABASE` statement for some dumped databases. (Bug#7358)

- Fixed that, when encountering a ``disk full'' or ``quota exceeded'' write error, `MyISAM` sometimes didn't sleep and retry the write, thus resulting in a corrupted table. (Bug#7714)

- Fixed that `--expire-log-days` was not honored if using only transactions. (Bug#7236)

- Fixed that a slave could crash after replicating many `ANALYZE TABLE`, `OPTIMIZE TABLE`, or `REPAIR TABLE` statements from the master. (Bug#6461, Bug#7658)

### C.2.5. Changements de la version 4.1.8 (14 Décembre 2004)

Fonctionnalités ajoutées ou modifiées :

Bogues corrigés :

### C.2.6. Changements de la version 4.1.7 (bientôt publiée)

Fonctionnalité ajoutée ou modifiée :

- InnoDB: Made `LOCK TABLES` behave by default like it did before MySQL 4.0.20 or 4.1.2: no `InnoDB` lock will be taken. Added a startup option and settable system variable `innodb_table_locks` for making `LOCK TABLE` acquire also `InnoDB` locks. See Section 15.17, « Restrictions sur les tables `InnoDB` ». (Bug#3299, Bug#5998)

Bogues corrigés :

- Fixed a bug with `FOUND_ROWS()` used together with `LIMIT` clause in prepared statements. (Bug#6088)

- Fixed a bug with `NATURAL JOIN` in prepared statements. (Bug#6046).

- Fixed a bug in join of tables from different databases having columns with identical names (prepared statements). (Bug#6050)

- Now implicit access to system time zone description tables (which happens when you set `time_zone` variable or use `CONVERT_TZ()` function) does not require any privileges. (Bug#6116)

- Fixed a bug which caused server crash when deprecated `libmysqlclient` functilon `mysql_create_db()` was called. (Bug#6081)

- Fixed `REVOKE ALL PRIVILEGES, GRANT OPTION FROM `user`` so that all privileges are revoked correctly. (Bug#5831). This corrects a case that the fix in 4.1.6 could miss.

- Fixed a bug that could cause MyISAM index corruption when key values start with character codes below `BLANK`. This was caused by the new key sort order in 4.1. (Bug#6151)

- Fixed a bug in the prepared statements protocol when wrong metadata was sent for `SELECT` statements not returning a result set (such as `SELECT ... INTO OUTFILE`). (Bug#6059)

- Fixed bug which allowed to circumvent missing UPDATE privilege if one had INSERT and SELECT privileges for table with primary key. (Bug#6173)

- Fixed a bug in `libmysqlclient` with wrong conversion of negative time values to strings. (Bug#6049).

- Fixed a bug in `libmysqlclient` with wrong conversion of zero date values (`0000-00-00`) to strings. (Bug#6058)

- Fixed a bug that caused the server to crash on attempt to prepare a statement with `RAND(?)`. (Bug#5985)

- Fixed a bug with handling of `DATE`, `TIME`, and `DATETIME` columns in the binary protocol. The problem is compiler-specific and could have been observed on HP-UX, AIX, Solaris9, when compiling with native compiler. (Bug#6025)

- Fixed a bug with handling of `TINYINT` columns in the binary protocol. The problem is specific to platforms where the C compiler has the `char` data type unsigned by default. (Bug#6024)

- Fixed problem introduced in MySQL 4.0.21 where a connection starting a transaction, doing updates, then `FLUSH TABLES WITH READ LOCK`, then `COMMIT`, would cause replication slaves to stop complaing about error 1223. Bug surfaced when using the InnoDB `innobackup` script. (Bug#5949)

### C.2.7. Changements de la version 4.1.6 (10 Octobre 2004)

Fonctionnalité ajoutée ou modifiée :

- Added option `--sigint-ignore` to the `mysql` command line client to make it ignore `SIGINT` signals (typically the result of the user pressing Control-C).

- InnoDB: Added the startup option and settable global variable `innodb_max_purge_lag` for delaying `INSERT`, `UPDATE` and `DELETE` operations when the purge operations are lagging. The default value of this parameter is zero, meaning that there are no delays. See Section 15.13, « Implémentation du multi-versionnage ».

- InnoDB: The `innodb_autoextend_increment` startup option that was introduced in release 4.1.5 was made a settable global variable. (Bug#5736)

- InnoDB: If `DROP TABLE` is invoked on an InnoDB table for which the `.ibd` file is missing, print to error log that the table was removed from the `InnoDB` data dictionary, and allow MySQL to delete the `.frm` file. Maybe `DROP TABLE` should issue a warning in this case.

- `TIMESTAMP` columns now can store `NULL` values. To create such a column, you must explicitly specify the `NULL` attribute in the column specification. (Unlike all other column types, `TIMESTAMP` columns are `NOT NULL` by default.)

- Now if `ALTER TABLE` converts one `AUTO_INCREMENT` column to another `AUTO_INCREMENT` column it preserves zero values (this includes the case that we don't change such column at all).

- Now if `ALTER TABLE` converts some column to `TIMESTAMP NOT NULL` column it converts `NULL` values to current timestamp value (One can still get old behavior by setting system `TIMESTAMP` variable to zero).

- On Windows, the MySQL configuration files included in the package now use `.ini` instead of `.cnf` as the file name suffix.

Bogues corrigés :

- Fixed a bug that caused the server to crash on attempt to execute a prepared statement with a subselect inside a boolean expression. (Bug#5987)

- Fixed a bug that caused the server to sometimes choose non-optimal execution plan for a prepared statement executed with changed placeholder values. (Bug#6042)

- InnoDB: Make the check for excessive semaphore waits tolerate glitches in the system clock (do not crash the server if the system time is adjusted while InnoDB is under load.). (Bug#5898)

- InnoDB: Fixed a bug in the InnoDB `FOREIGN KEY` parser that prevented `ALTER TABLE` of tables containing ‘`#`’ in their names. (Bug#5856)

- InnoDB: Fixed a bug that prevented `ALTER TABLE `t` DISCARD TABLESPACE` from working. (Bug#5851)

- InnoDB: `SHOW CREATE TABLE` now obeys the `SET SQL_MODE=ANSI` and `SET SQL_QUOTE_SHOW_CREATE=0` settings. (Bug#5292)

- InnoDB: Fixed a bug that caused `CREATE TEMPORARY TABLE ... ENGINE=InnoDB` to terminate mysqld when running in `innodb_file_per_table` mode. Per-table tablespaces for temporary tables from now on are created in the temporary directory of mysqld. (Bug#5137)

- InnoDB: Fixed some (not all) UTF-8 bugs in column prefix indexes. (Bug#5975)

- InnoDB: If one updated a column so that its size changed, or updated it to an externally stored (`TEXT` or `BLOB`) value, then ANOTHER externally stored column would show up as 512 bytes of good data + 20 bytes of garbage in a consistent read that fetched the old version of the row. (Bug#5960)

- InnoDB: Change error code to `HA_ERR_ROW_IS_REFERENCED` if we cannot `DROP` a parent table referenced by a `FOREIGN KEY` constraint; this error number is less misleading than the previous number `HA_ERR_CANNOT_ADD_FOREIGN`, but misleading still. (Bug#6202)

- Fixed `REVOKE ALL PRIVILEGES, GRANT OPTION FROM `user`` so that all privileges are revoked correctly. (Bug#5831)

- Fixed a bug that caused the server to crash when character set conversion was implicitly used in prepared mode; for example, as in `'abc' LIKE CONVERT('abc' as utf8)`. (Bug#5688)

- The `mysql_change_user()` C API function now frees all prepared statements associated with the connection. (Bug#5315)

- Fixed a bug when inserting `NULL` into an `AUTO_INCREMENT` column failed, when using prepared statements. (Bug#5510)

- Fixed slave SQL thread so that the `SET COLLATION_SERVER...` statements it replicates don't advance its position (so that if it gets interrupted before the actual update query, it later redoes the `SET`). (Bug#5705)

- Fixed that if the slave SQL thread found a syntax error in a query (which should be rare, as the master parsed it successfully), it stops. (Bug#5711)

- Fixed that if a write to a `MyISAM` table fails because of a full disk or an exceeded disk quota, it prints a message to the error log every 10 minutes, and waits until disk space becomes available. (Bug#3248)

- Now MySQL does not prefer columns, which are mentioned in select list but are renamed, over columns from other tables participating in `FROM` clause when it resolves `GROUP BY` clause (e.g. `SELECT t1.a AS c FROM t1, t2 ORDER BY a` produces an error if both `t1` and `t2` tables contain `a` column). (Bug#4302)

- Behavior of `ALTER TABLE` converting column containing `NULL` values to `AUTO_INCREMENT` column is no longer affected by `NO_AUTO_VALUE_ON_ZERO` mode. (Bug#5915).

### C.2.8. Changements de la version 4.1.4 (16 Septembre 2004)

Fonctionnalité ajoutée ou modifiée :

- `InnoDB`: Added configuration option `innodb_autoextend_increment` for setting the size in megabytes by which `InnoDB` tablespaces are extended when they become full. The default value is 8, corresponding to the fixed increment of 8MB in previous versions of MySQL.

Bogues corrigés :

- Fixed a bug which caused the server to crash on attempt to execute a prepared statement with `BETWEEN ? AND ?` and a datetime column. (Bug#5748)

- Fixed name resolving of external fields of subqueries if subquery placed in select list of query with grouping. (Bug#5326)

- Fixed detection of using same table for updating and selecting in multi-update queries. (Bug#5455)

- The values of the `max_sort_length`, `sql_mode`, and `group_concat_max_len` system variables now are stored in the query cache with other query information to avoid returning an incorrect result from the query cache. (Bug#5394) (Bug#5515)

- Fixed syntax analyzer with `sql_mode=IGNORE_SPACE`. It happened to take phrases like `default .07` as `identifier.identifier`. (Bug#5318)

- Fixed illegal internal field length of user variables of integer type. This showed up when creating a table as `SELECT @`var_name``. (Bug#4788)

- Fixed a buffer overflow in prepared statements API (libmysqlclient) when a statement containing thousands of placeholders was executed. (Bug#5194)

- Fixed a bug in the server when after reaching a certain limit of prepared statements per connection (97), statement ids began to overlap, so occasionally wrong statements were chosen for execution. (Bug#5399)

- Fixed a bug in prepared statements when `LIKE` used with arguments in different character sets crashed server on first execute. (Bug#4368)

- Fixed a bug in prepared statements when providing '0000-00-00' date to a parameter lead to server crash. (Bug#4231, Bug#4562)

- Fixed a bug in `OPTIMIZE TABLE` that could cause table corruption on `FULLTEXT` indexes. (Bug#5327)

- InnoDB: Fixed a bug that InnoDB only allowed a maximum of 1000 connections inside InnoDB at the same time. A higher number could cause an assertion failure in sync0arr.c, line 384. Now we allow 1000, 10000, or 50000, depending on the buffer pool size. (Bug#5414)

### C.2.9. Changements de la version 4.1.4 (26 Août 2004)

Note: To fix a compile problem on systems that do not have `automake` 1.7 installed, an updated 4.1.4a source tarball has been published. In addition to resolving this `automake` dependency (Bug#5319), it also fixes some reported `libedit` compile errors when using a non-`gcc` compiler (Bug#5353).

Fonctionnalité ajoutée ou modifiée :

- Made internal representation of `TIMESTAMP` values in `InnoDB` in 4.1 to be the same as in 4.0. This difference resulted in incorrect datetime values in `TIMESTAMP` columns in `InnoDB` tables after an upgrade from 4.0 to 4.1. (Bug#4492) Warning: extra steps during upgrade required! Unfortunately this means that if you are upgrading from 4.1.x, where x <= 3, to 4.1.4 you should use mysqldump for saving and then restoring your `InnoDB` tables with `TIMESTAMP` columns.

- The mysqld-opt Windows server was renamed to mysqld. This completes the Windows server renaming begun in MySQL 4.1.2. See Section 2.2.8.1, « Choisir un serveur MySQL sur Windows ».

- Added Latin language collations for the `ucs2` and `utf8` Unicode character sets. These are called `ucs2_roman_ci` and `utf8_roman_ci`.

- Corrected the name of the Mac OS X StartupItem script (it must match the name of the subdirectory, which was renamed to `MySQLCOM` in MySQL 4.1.2). Thanks to Bryan McCormack for reporting this.

- Added `--start-datetime`, `--stop-datetime`, `--start-position`, and `--stop-position` options to `mysqlbinlog`. These make point-in-time recovery easier.

- Killing a `CHECK TABLE` statement does not result in the table being marked as ``corrupted'' any more; the table remains as if `CHECK TABLE` had not even started. See Section 13.5.4.3, « Syntaxe de `KILL` ».

- Made the MySQL server ignore `SIGHUP` and `SIGQUIT` on Mac OS X 10.3. This is needed because under this OS, the MySQL server receives lots of these signals (reported as Bug#2030).

Bogues corrigés :

- Fixed a bug that caused libmysql to crash when attempting to fetch a value of `MEDIUMINT` column. (Bug#5126)

- Fixed a bug that caused the MySQL server to crash when attempting to execute a prepared statement with `SELECT ... INTO @var` for a second time. (Bug#5034)

- Fixed execution of optimized `IN` subqueries that use compound indexes. (Bug#4435)

- Prohibited resolving of table fields in inner queries if fields do not take part in grouping for queries with grouping (inside aggregate function arguments, all table fields are still allowed). (Bug#4814)

- Fixed a crash after `SLAVE STOP` if the IO thread was in a special state. (Bug#4629)

- Fixed an old bug in concurrent accesses to `MERGE` tables (even one `MERGE` table and `MyISAM` tables), that could have resulted in a crash or hang of the server. (Bug#2408)

- Fixed a bug that caused server crash on attempt to execute for a second time a prepared statement with `NOT` in `WHERE` or `ON` clauses. (Bug#4912)

- `MATCH ... AGAINST` now works in a subquery. (Bug#4769)

- Fixed a bug that omitted the `.err` extension of the error log file (`--log-error`) when the hostname contained a domain name. The domain name is now replaced by the extension. (Bug#4997)

- Fixed a crash in myisamchk. (Bug#4901)

- Fixed a bug which caused server crash if one used the `CONVERT_TZ()` function with time zone described in database as parameter and this time zone was not used before. (Bug#4508)

- Support for `%T, %r, %V, %v` and `%X, %x` format specifiers was added to `STR_TO_DATE()` function. (Bug#4756)

- Fixed a bug (hang) in `NATURAL JOIN` where joined table had no common column. (Bug#4807)

- Fixed a crash caused by `UNHEX(NULL)`. (Bug#4441)

- mysql_fix_privilege_tables didn't correctly handle the argument of its `--password=#` option. (Bug#4240, Bug#4543)

- Fixed that mysqlbinlog --read-from-remote-server sometimes couldn't accept 2 binary logs on command line. (Bug#4507)

- Fixed that mysqlbinlog --position --read-from-remote-server had wrong `# at` lines. (Bug#4506)

- If `CREATE TEMPORARY TABLE t SELECT` failed while loading the data, the temporary table was not dropped. (Bug#4551)

- Fixed that when a multiple-table `DROP TABLE` failed to drop a table on the master server, the error code was not written to the binary log. (Bug#4553)

- When the slave SQL thread was replicating a `LOAD DATA INFILE` statement, it didn't show the statement in the output of `SHOW PROCESSLIST`. (Bug#4326)

- Fixed an assertion failure when reading the grant tables (Bug#4407)

- Fixed that `CREATE TABLE ... TYPE=HEAP ... AS SELECT...` caused replication slave to stop. (Bug#4971)

- Fixed that `mysql_options(...,MYSQL_OPT_LOCAL_INFILE,...)` failed to disable `LOAD DATA LOCAL INFILE`. (Bug#5038)

- Fixed that `disable-local-infile` option had no effect if client read it from a configuration file using `mysql_options(...,MYSQL_READ_DEFAULT,...)`. (Bug#5073)

- Fixed that `SET GLOBAL SYNC_BINLOG` did not work on some platforms (Mac OS X). (Bug#5064)

- Fixed that mysql-test-run failed on the `rpl_trunc_binlog` test if running test from the installed (the target of 'make install') directory. (Bug#5050)

- Fixed that mysql-test-run failed on the `grant_cache` test when run as Unix user 'root'. (Bug#4678)

- Fixed an unlikely deadlock which could happen when using `KILL`. (Bug#4810)

- Fixed a crash when one connection got `KILL`ed while it was doing `START SLAVE`. (Bug#4827)

- Made `FLUSH TABLES WITH READ LOCK` block `COMMIT` if server is running with binary logging; this ensures that the binary log position is trustable when doing a full backup of tables and the binary log. (Bug#4953)

- Fixed that the counter of an `auto_increment` column was not reset by `TRUNCATE TABLE` if the table was a temporary table. (Bug#5033)

- Fixed bug which caused error to be reported when column from `ORDER BY` clause was present in two tables participating in `SELECT` even if the second instance of column in select list was renamed. (Bug#4302)

### C.2.10. Changements de la version 4.1.3 (pas encore publiée)

Fonctionnalité ajoutée ou modifiée :

Bogues corrigés :

- Fixed a crash of `mysqld` that was started with binary logging disabled, but with non-zero `expire_logs_days` variable. (Bug#3807)

### C.2.11. Changements de la version 4.1.2

Fonctionnalité ajoutée ou modifiée :

- Added explanation of hidden `SELECT` of `UNION` in output of `EXPLAIN SELECT` statement.

- `mysql` command-line client now supports multiple `-e` options. (Bug#591)

- New `myisam_data_pointer_size` system variable. See Section 5.2.3, « Variables serveur système ».

- The `--log-warnings` server option now is enabled by default. Disable with `--skip-log-warnings`.

- The `--defaults-file=file_name` option now requires that the filename must exist (safety fix). (Bug#3413)

- `mysqld_multi` now creates the log in datadir (from `[mysqld]` section in `my.cnf` or compiled in), not in `/tmp` - vulnerability id CAN-2004-0388. Thanks to Christian Hammers from Debian Security Team for reporting this!

- Warning: Incompatible change! String comparison now works according to the SQL standard. Because we have that `'a' = 'a '` then from it must follow that `'a' > 'a\t'`. (The latter was not the case before 4.1.2.) To implement it, we had to change how storage engines compare strings internally. As a side effect, if you have a table where a `CHAR` or `VARCHAR` column in some row has a value with the last character less than `ASCII(32)`, you will have to repair this table. `CHECK TABLES` will tell you if this problem exists. (Bug#3152)

- Added support for `DEFAULT CURRENT_TIMESTAMP` and for `ON UPDATE CURRENT_TIMESTAMP` specifications for `TIMESTAMP` columns. Now you can explicitly say that a `TIMESTAMP` column should be set automatically to the current timestamp for `INSERT` and/or `UPDATE` statements, or even prevent the column from updating automatically. Only one column with such an auto-set feature per table is supported. `TIMESTAMP` columns created with earlier versions of MySQL behave as before. Behavior of `TIMESTAMP` columns that were created without explicit specification of default/on as earlier depends on its position in table: If it is the first `TIMESTAMP` column, it will be treated as having been specified as `TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP`. In other cases, it would be treated as a `TIMESTAMP DEFAULT 0` column. `NOW` is supported as an alias for `CURRENT_TIMESTAMP`. Warning: Incompatible change! Unlike in previous versions, explicit specification of default values for `TIMESTAMP` column is never ignored and turns off the auto-set feature (unless you have `CURRENT_TIMESTAMP` as the default).

- Warning: Incompatible change! Renamed prepared statements C API functions:

  Old Name | New Name
  `mysql_bind_param()` | `mysql_stmt_bind_param()`
  `mysql_bind_result()` | `mysql_stmt_bind_result()`
  `mysql_prepare()` | `mysql_stmt_prepare()`
  `mysql_execute()` | `mysql_stmt_execute()`
  `mysql_fetch()` | `mysql_stmt_fetch()`
  `mysql_fetch_column()` | `mysql_stmt_fetch_column()`
  `mysql_param_count()` | `mysql_stmt_param_count()`
  `mysql_param_result()` | `mysql_stmt_param_metadata()`
  `mysql_get_metadata()` | `mysql_stmt_result_metadata()`
  `mysql_send_long_data()` | `mysql_stmt_send_long_data()`

  Now all functions that operate with a `MYSQL_STMT` structure begin with the prefix `mysql_stmt_`.

- Warning: Incompatible change! The signature of the `mysql_stmt_prepare()` function was changed to `int mysql_stmt_prepare(MYSQL_STMT *stmt, const char *query, unsigned long length)`. To create a `MYSQL_STMT` handle, you should use the `mysql_stmt_init()` function.

- `SHOW GRANTS` with no `FOR` clause or with `FOR CURRENT_USER()` shows the privileges for the current session.

- The improved character set support introduced in MySQL 4.1.0 for the `MyISAM` and `HEAP` storage engines is now available for `InnoDB` as well.

- A name of ``Primary'' no longer can be specified as an index name. (That name is reserved for the `PRIMARY KEY` if the table has one.) (Bug#856)

- MySQL now issues a warning when a `SET` or `ENUM` column with duplicate values in the list is created. (Bug#1427)

- Now `SQL_SELECT_LIMIT` variable has no influence on subqueries. (Bug#2600)

- `UNHEX()` function implemented. See Section 12.3, « Fonctions de chaînes de caractères ».

- History in command line client does not store multiple copies of identical queries that are run consecutively.

- Multi-line queries in the command line client now are stored as a single line.

- `UUID()` function implemented. Note that it does not work with replication yet. See Section 12.8.4, « Fonctions diverses ».

- Prepared statements with all types of subqueries fixed.

- MySQL now supports up to 64 keys per table.

- `MyISAM` tables now support keys up to 1000 bytes long.

- `MyISAM` and `InnoDB` tables now support index prefix lengths up to 1000 bytes long.

- If you try to create a key with a key part that is too long, and it is safe to auto-truncate it to a smaller length, MySQL now does so. A warning is generated, rather than an error.

- The `ft_boolean_syntax` variable now can be changed while the server is running. See Section 5.2.3, « Variables serveur système ».

- `REVOKE ALL PRIVILEGES, GRANT FROM user_list` is changed to a more consistent `REVOKE ALL PRIVILEGES, GRANT OPTION FROM user_list`. (Bug#2642)

- Internal string-to-number conversion now supports only SQL:2003 compatible syntax for numbers. In particular, `'0x10'+0` will not work anymore. (Actually, it worked only on some systems before, such as Linux. It did not work on others, such as FreeBSD or Solaris. Making these queries OS-independent was the goal of this change). Use `CONV()` to convert hexadecimal numbers to decimal. E.g. `CONV(MID('0x10',3),16,10)+0`.

- `mysqlhotcopy` now works on NetWare.

- `ALTER TABLE DROP PRIMARY KEY` no longer drops the first `UNIQUE` index if there is no primary index. (Bug#2361)

- Added `latin1_spanish_ci` (Modern Spanish) collation for the `latin1` character set.

- Added the `ENGINE` table option as a synonym for the `TYPE` option for `CREATE TABLE` and `ALTER TABLE`.

- Added the `--default-storage-engine` server option as a synonym for `--default-table-type`.

- Added the `storage_engine` system variable as a synonym for `table_type`.

- Added `init_connect` and `init_slave` server variables. The values should be SQL statements to be executed when each client connects or each time a slave's SQL thread starts, respectively.

- C API enhancement: `SERVER_QUERY_NO_INDEX_USED` and `SERVER_QUERY_NO_GOOD_INDEX_USED` flags are now set in the `server_status` field of the `MYSQL` structure. It is these flags that make the query to be logged as slow if `mysqld` was started with `--log-slow-queries --log-queries-not-using-indexes`.

- For replication of `MEMORY` (`HEAP`) tables: Made the master automatically write a `DELETE FROM` statement to its binary log when a `MEMORY` table is opened for the first time since master's startup. This is for the case where the slave has replicated a non-empty `MEMORY` table, then the master is shut down and restarted: the table is now empty on master; the `DELETE FROM` empties it on slave too. Note that even with this fix, between the master's restart and the first use of the table on master, the slave still has out-of-date data in the table. But if you use the `init-file` option to populate the `MEMORY` table on the master at startup, it ensures that the failing time interval is zero. (Bug#2477)

- When a session having open temporary tables terminates, the statement automatically written to the binary log is now `DROP TEMPORARY TABLE IF EXISTS` instead of `DROP TEMPORARY TABLE`, for more robustness.

- The MySQL server now returns an error if `SET SQL_LOG_BIN` or `SET SQL_LOG_UPDATE` is issued by a user without the `SUPER` privilege (in previous versions it just silently ignored the statement in this case).

- Changed that when the MySQL server has binary logging disabled (that is, no `log-bin` option was used) then no transaction binlog cache is allocated for connections (this should save `binlog_cache_size` bytes of memory (32 kilobytes by default) for every connection).

- Added `Binlog_cache_use` and `Binlog_cache_disk_use` status variables that count the number of transactions that used transaction binary log and that had to flush this temporary binary log to disk instead of using only buffer in memory. They can be used for tuning the `binlog_cache_size` system variable.

- Added option `--replicate-same-server-id`.

- The Mac OS X Startup Item has been moved from the directory `/Library/StartupItems/MySQL` to `/Library/StartupItems/MySQLCOM` to avoid a file name collision with the MySQL Startup Item installed with Mac OS X Server. See Section 2.8.2, « Notes relatives à Mac OS X ».

Bogues corrigés :

- Fixed check of `EXPLAIN` of `UNION`. (Bug#3639)

- Fixed a bug in a query that used `DISTINCT` and `ORDER BY` by column's real name, while the column had an alias, specified in `SELECT` clause. (Bug#3681)

- Fixed crash of `group_concat` on expression with `ORDER BY` and external `ORDER BY` in a query. (Bug#3752)

- Fixed a bug in `ALL`/`SOME` subqueries in case of optimisation (key field present in subquery). (Bug#3646)

- Fixed a bug in `SHOW GRANTS` and `EXPLAIN SELECT` character set conversion. (Bug#3403)

- Prepare statements parameter do not cause error message as fields used in select list but not included in `ORDER BY` list.

- `UNION` statements did not consult `SQL_SELECT_LIMIT` value when set. This is now fixed properly, which means that this limit is applied to the top level query, unless `LIMIT` for entire `UNION` is used.

- Fixed a bug in multiple-table `UPDATE` statements that resulted in an error when one of the tables was not updated but was used in the nested query, contained therein.

- Fixed `mysql_stmt_send_long_data()` behavior on second execution of prepared statement and in case when long data had zero length. (Bug#1664)

- Fixed crash on second execution of prepared statement with `UNION`. (Bug#3577)

- Fixed incorrect results of aggregate functions in subquery with empty result set. (Bug#3505)

- You can now call `mysql_stmt_attr_set(..., STMT_ATTR_UPDATE_MAX_LENGTH)` to tell the client library to update `MYSQL_FIELD->max_length` when doing `mysql_stmt_store_result()`. (Bug#1647).

- Added support for unsigned integer types to prepared statement API (Bug#3035).

- Fixed crash in prepared statements when subquery in the `FROM` clause with parameter used. (Bug#3020)

- Fixed unknown error when negative value bind to unsigned. (Bug#3223)

- Fixed aggregate function in prepared statements. (Bug#3360)

- Incorrect error message when wrong table used in multiple-table `DELETE` statement in prepared statements. (Bug#3411)

- Requiring `UPDATE` privilege for tables which will not be updated in multiple-table `UPDATE` statement in prepared statements.

- Fixed prepared statement support for `INSERT`, `REPLACE`, `CREATE`, `DELETE`, `SELECT`, `DO`, `SET` and `SHOW`. All other commands are prohibited via prepared statement interface. (Bug#3398, Bug#3406, Bug#2811)

- Fixed a lot of bugs in `GROUP_CONCAT()`. (Bug#2695, Bug#3381, Bug#3319)

- Added optimization that allows for prepared statements using a large number of tables or tables with a large number of columns to be re-executed significantly faster. (Bug#2050)

- Fixed bug that caused execution of prepared statements to fail then table that this statement were using left table cache. This bug showed up as if this prepared statement used random garbage as column names or as server crashes. (Bug#3307)

- Fixed a problem resulting from setting the `character_set_results` variable to `NULL`. (Bug#3296)

- Fixed query cache statistics.

- Fixed bug in `ANALYZE TABLE` on a `BDB` table inside a transaction that hangs server thread. (Bug#2342)

- Fixed a symlink vulnerability in `mysqlbug` script. (Bug#3284)

- Fixed a bug in parallel repair (`myisamchk -p`, `myisam_repair_threads`); sometimes the repair process failed to repair a table. (Bug#1334)

- A query that uses both `UNION [DISTINCT]` and `UNION ALL` now works correctly. (Bug#1428)

- Table default character set affects `LONGBLOB` columns. (Bug#2821)

- `CONCAT_WS()` makes the server die in case of illegal mix of collations. (Bug#3087)

- UTF8 charset breaks joins with mixed column/string constant. (Bug#2959)

- Fixed `DROP DATABASE` to report number of tables deleted.

- Fixed memory leak in the client library when statement handle was freed on closed connection (call to `mysql_stmt_close` after `mysql_close`). (Bug#3073)

- Fixed server segfaults when processing malformed prepared statements commands. (Bug#2795, Bug#2274)

- Fixed using subqueries with `OR` and `AND` functions. (Bug#2838)

- Fixed comparison of tables/database names with `--lower_case_table_names` option. (Bug#2880)

- Removed try to check `NULL` if index built on column where `NULL` is impossible in `IN` subquery optimization. (Bug#2393)

- Fixed incorrect parsing of subqueries in the `FROM` clause. (Bug#2421)

- Fixed processing of `RAND()` in subqueries with static tables. (Bug#2645)

- Fixed bug with quoting of table names in `mysqldump` for various values of `sql_mode` of server. (Bug#2591)

- Fixed bug with storing values that are out of range for `DOUBLE` and `FLOAT` columns. (Bug#2082)

- Fixed bug with compiling `--with-pstack` with binutils 2.13.90. (Bug#1661)

- Fixed a bug in the `GRANT` system. When a password was assigned to an account at the global level and then privileges were granted at the database level (without specifying any password), the existing password was replaced temporarily in memory until the next `FLUSH PRIVILEGES` operation or the server was restarted. (Bug#2953)

- Fixed a bug in full-text search on multi-byte character set (such as UTF8) that appeared when a search word was shorter than a matching word from the index (for example, searching for ``Uppsala'' when table data contain ``Uppsa*la''). (Bug#3011)

- Fixed a bug that made `Max_used_connections` to be less than the actual maximum number of connections in use simultaneously.

- Fixed calculation of `Index_length` in `HEAP` table status for `BTREE` indexes. (Bug#2719)

- Fixed `mysql_stmt_affected_rows()` call to always return number of rows affected by given statement. (Bug#2247)

- Fixed crash in `MATCH ... AGAINST()` on a phrase search operator with a missing closing double quote. (Bug#2708)

- Fixed output of `mysqldump --tab`. (Bug#2705)

- Fix for a bug in `UNION` operations that prevented proper handling of `NULL` columns. This happened only if a column in the first `SELECT` node was `NOT NULL`. (Bug#2508)

- Fix for a bug in `UNION` operations with `InnoDB` storage engine, when some columns from one table where used in one `SELECT` statement and some were used in another `SELECT` statement. (Bug#2552)

- Fixed a few years old bug in the range optimizer that caused a segmentation fault on some very rare queries. (Bug#2698)

- Fixed bug with `SHOW CREATE TABLE ...` which didn't properly double quotes. (Bug#2593)

- Queries with subqueries in `FROM` clause locks all tables at once for now. This also fixed bugs in `EXPLAIN` of subqueries in `FROM` output. (Bug#2120)

- Fixed bug with `mysqldump` not quoting ``tricky'' names correctly. (Bug#2592)

- Fix for a bug that prevented table / column privileges from being loaded on startup. (Bug#2546)

- Fixed bug in replication with `CREATE TABLE ... LIKE ...` that resulted in a statement not being written to the binary log. (Bug#2557)

- Fixed memory leak in `INSERT ... ON DUPLICATE KEY UPDATE ...`. (Bug#2438)

- Fixed bug in the parser, making the syntax `CONVERT(expr,type)` legal again.

- Fixed parsing of short-form IP addresses in `INET_ATON()`. (Bug#2310)

- Fixed a bug in `CREATE ... SELECT` that sometimes caused a string column with a multi-byte character set (such as `utf8`) to have insufficient length to hold the data.

- Fixed a rare table corruption on adding data (`INSERT`, `REPLACE`, `UPDATE`, etc. but not `DELETE`) to a `FULLTEXT` index. (Bug#2417)

- Compile the `MySQL-client` RPM package against `libreadline` instead of `libedit`. (Bug#2289)

- Fix for a crashing bug that was caused by not setting `vio_timeout()` virtual function for all protocols. This bug occurred on Windows. (Bug#2025)

- Fix for a bug that caused `mysql` client program to erroneously cache the value of the current database. (Bug#2025)

- Fix for a bug that caused client/server communication to be broken when `mysql_set_server_option()` or `mysql_get_server_option()` were invoked. (Bug#2207)

- Fix for a bug that caused wong results when `CAST()` was applied on `NULL` to signed or unsigned integer column. (Bug#2219)

- Fix for a crashing bug that occurred in the `mysql` client program when database name was longer then expected. (Bug#2221)

- Fixed a bug in `CHECK TABLE` that sometimes resulted in a spurious error `Found key at page ... that points to record outside datafile` for a table with a `FULLTEXT` index. (Bug#2190)

- Fixed bug in `GRANT` with table-level privilege handling. (Bug#2178)

- Fixed bug in `ORDER BY` on a small column. (Bug#2147)

- Fixed a bug with the `INTERVAL()` function when 8 or more comparison arguments are provided. (Bug#1561)

- Packaging: Fixed a bug in the Mac OS PKG `postinstall` script (`mysql_install_db` was called with an obsolete argument).

- Packaging: Added missing file `mysql_create_system_tables` to the server RPM package. This bug was fixed for the 4.1.1 RPMs by updating the MySQL-server RPM from `MySQL-server-4.1.1-0` to `MySQL-server-4.1.1-1`. The other RPMs were not affected by this change.

- Fixed a bug in `myisamchk` and `CHECK TABLE` that sometimes resulted in a spurious error `Found key at page ... that points to record outside datafile` for a table with a `FULLTEXT` index. (Bug#1977)

- Fixed a hang in full-text indexing of strings in multi-byte (all besides `utf8`) charsets. (Bug#2065)

- Fixed a crash in full-text indexing of UTF8 data. (Bug#2033)

- Replication: a rare race condition in the slave SQL thread that could lead to an incorrect complaint that the relay log is corrupted. (Bug#2011)

- Replication: If a client connects to a slave server and issues an administrative statement for a table (for example, `OPTIMIZE TABLE` or `REPAIR TABLE`), this could sometimes stop the slave SQL thread. This does not lead to any corruption, but you must use `START SLAVE` to get replication going again. (Bug#1858)

- Replication: in the slave SQL thread, a multiple-table `UPDATE` could produce an incorrect complaint that some record was not found in one table, if the `UPDATE` was preceded by a `INSERT ... SELECT`. (Bug#1701)

- Replication: sometimes the master gets a non-fatal error during the execution of a statement but finally the statements succeeds (for example, a write to a `MyISAM` table first receives "no space left on device" but is able to finally complete, see Section A.4.3, « Comment MySQL gère un disque plein »); the bug was that the master forgot to reset the error code to 0 after success, so the error code got into its binary log, thus making the slave giving false alarms like "did not get the same error as on master". (Bug#2083)

- Removed a misleading "check permissions on master.info" from a replication error message, because the cause of the problem could be different from permissions. (Bug#2121)

- Fixed a crash when the replication slave was unable to create the first relay log. (Bug#2145)

- `ALTER DATABASE` caused the client to hang if the database did not exist. (Bug#2333)

- Multiple-table `DELETE` statements were never replicated by the slave if there were any `replicate-*-table` options. (Bug#2527)

- Fixed bug in `ALTER TABLE RENAME`, when rename to the table with the same name in another database silently dropped destination table if it existed. (Bug#2628)

- The MySQL server did not report any error if the query (submitted through `mysql_real_query()` or `mysql_prepare()`) was terminated by garbage characters (which can happen if you pass a wrong `length` parameter to `mysql_real_query()` or `mysql_prepare()`); the result was that the garbage characters were written into the binary log. (Bug#2703)

- Fixed bug in client library which caused `mysql_fetch` and `mysql_stmt_store_result()` to hang if they were called without prior call of `mysql_execute()`. Now they give an error instead. (Bug#2248)

- Made clearer the error message which one gets when an update is refused because of the `read-only` option. (Bug#2757)

- Fixed that `replicate-wild-*-table` rules apply to `ALTER DATABASE` when the table pattern is '%', like it is already the case for `CREATE DATABASE` and `DROP DATABASE`. (Bug#3000)

- Fixed that when a `Rotate` event is found by the slave SQL thread in the middle of a transaction, the value of `Relay_Log_Pos` in `SHOW SLAVE STATUS` remains correct. (Bug#3017)

- Corrected the master's binary log position that `InnoDB` reports when it is doing a crash recovery on a slave server. (Bug#3015)

- Changed the column `Seconds_Behind_Master` in `SHOW SLAVE STATUS` to never show a value of -1. (Bug#2826)

- Changed that when a `DROP TEMPORARY TABLE` statement is automatically written to the binary log when a session ends, the statement is recorded with an error code of value zero (this ensures that killing a `SELECT` on the master does not result in a superfluous error on the slave). (Bug#3063)

- Changed that when a thread handling `INSERT DELAYED` (also known as a `delayed_insert` thread) is killed, its statements are recorded with an error code of value zero (killing such a thread does not endanger replication, so we thus avoid a superfluous error on the slave). (Bug#3081)

- Fixed deadlock when two `START SLAVE` commands were run at the same time. (Bug#2921)

- Fixed that a statement never triggers a superfluous error on the slave, if it must be excluded given the `replicate-*` options. The bug was that if the statement had been killed on the master, the slave would stop. (Bug#2983)

- The `--local-load` option of `mysqlbinlog` now requires an argument.

- Fixed a segmentation fault when running `LOAD DATA FROM MASTER` after `RESET SLAVE`. (Bug#2922)

- `mysqlbinlog --read-from-remote-server` read all binary logs following the one that was requested. It now stops at the end of the requested file, the same was it does when reading a local binary log. (Bug#3204)

- Fixed `mysqlbinlog --read-from-remote-server` to print the exact positions of events in the "at #" lines. (Bug#3214)

- Fixed a rare error condition that caused the slave SQL thread spuriously to print the message `Binlog has bad magic number` and stop when it was not necessary to do so. (Bug#3401)

- Fixed the `Exec_master_log_pos` column and its disk image in the `relay-log.info` file to be correct if the master had version 3.23. (The value was too big by six bytes.) This bug does not exist in MySQL 5.0. (Bug#3400)

- Fixed `mysqlbinlog` not to forget to print a `USE` statement under rare circumstances where the binary log contained a `LOAD DATA INFILE` statement. (Bug#3415)

- Fixed a memory corruption when replicating a `LOAD DATA INFILE` when the master had version 3.23. Some smaller problems remain in this setup, See Section 6.7, « Fonctionnalités de la réplication et problèmes connus ». (Bug#3422)

- Multiple-table `DELETE` statements were always replicated by the slave if there were some `replicate-*-ignore-table` options and no `replicate-*-do-table` options. (Bug#3461)

- Fixed a crash of the MySQL slave server when it was built with `--with-debug` and replicating itself. (Bug#3568)

- Fixed that in some replication error messages, a very long query caused the rest of the message to be invisible (truncated), by putting the query last in the message. (Bug#3357)

### C.2.12. Changements de la version 4.1.1 (01 décembre 2003)

This release includes all fixes in MySQL 4.0.16 and most of the fixes in MySQL 4.0.17.

Fonctionnalité ajoutée ou modifiée :

- New `CHECKSUM TABLE` statement for reporting table checksum values.

- Added `character_set_client`, `character_set_connection`, `character_set_database`, `character_set_results`, `character_set_server`, `character_set_system`, `collation_connection`, `collation_database`, and `collation_server` system variables to provide information about character sets and collations.

- It is now possible to create multiple key caches, assign table indexes to particular caches, and to preload indexes into caches. See Section 13.5.4.1, « Syntaxe de `CACHE INDEX` ». See Section 13.5.4.4, « Syntaxe de `LOAD INDEX INTO CACHE` ». Structured system variables are introduced as a means of grouping related key cache parameters. See Section 9.4.1, « Variables système structurées ».

- New `COERCIBILITY()` function to return the collation coercibility of a string.

- The `--quote-names` option for `mysqldump` now is enabled by default.

- `mysqldump` now includes a statement in the dump output to set `FOREIGN_KEY_CHECKS` to 0 to avoid problems with tables having to be reloaded in a particular order when the dump is reloaded. The existing `FOREIGN_KEY_CHECKS` value is saved and restored.

- Important note: If you upgrade to `InnoDB`-4.1.1 or higher, you cannot downgrade to a version lower than 4.1.1 any more! That is because earlier versions of `InnoDB` are not aware of multiple tablespaces.

- One can revoke all privileges from a user with `REVOKE ALL PRIVILEGES, GRANT FROM user_list`.

- Added `IGNORE` option for `DELETE` statement.

- The MySQL source distribution now also includes the MySQL Internals Manual `internals.texi`.

- Added `mysql_set_server_option()` C API client function to allow multiple statement handling in the server to be enabled or disabled.

- The `mysql_next_result()` C API function now returns `-1` if there are no more result sets.

- Renamed `CLIENT_MULTI_QUERIES` connect option flag to `CLIENT_MULTI_STATEMENTS`. To allow for a transition period, the old option will continue to be recognized for a while.

- Require `DEFAULT` before table and database default character set. This enables us to use `ALTER TABLE tbl_name ... CHARACTER SET=...` to change the character set for all `CHAR`, `VARCHAR`, and `TEXT` columns in a table.

- Added `MATCH ... AGAINST( ... WITH QUERY EXPANSION)` and the `ft_query_expansion_limit` server variable.

- Removed unused `ft_max_word_len_for_sort` system variable.

- Removed unused `ft_max_word_len_for_sort` variable from `myisamchk`.

- Full-text search now supports multi-byte character sets and the Unicode `utf8` character set. (The Unicode `ucs2` character set is not yet supported.)

- Phrase search in `MATCH ... AGAINST ( ... IN BOOLEAN MODE)` no longer matches partial words.

- Added aggregate function `BIT_XOR()` for bitwise XOR operations.

- Replication over SSL now works.

- The `START SLAVE` statement now supports an `UNTIL` clause for specifying that the slave SQL thread should be started but run only until it reaches a given position in the master's binary logs or in the slave's relay logs.

- Produce warnings even for single-row `INSERT` statements, not just for multiple-row `INSERT` statements. Previously, it was necessary to set `SQL_WARNINGS=1` to generate warnings for single-row statements.

- Added `delimiter` (`\d`) command to the `mysql` command-line client for changing the statement delimiter (terminator). The default delimiter is semicolon.

- `CHAR`, `VARCHAR`, and `TEXT` columns now have lengths measured in characters rather than in bytes. The character size depends on the column's character set. This means, for example, that a `CHAR(n)` column for a multi-byte character set will take more storage than before. Similarly, index values on such columns are measured in characters, not bytes.

- `LIMIT` no longer accepts negative arguments (they used to be treated as very big positive numbers before).

- The `DATABASE()` function now returns `NULL` rather than the empty string if there is no database selected.

- Added `--sql-mode=NO_AUTO_VALUE_ON_ZERO` option to suppress the usual behavior of generating the next sequence number when zero is stored in an `AUTO_INCREMENT` column. With this mode enabled, zero is stored as zero; only storing `NULL` generates a sequence number.

- Warning: Incompatible change! Client authentication now is based on 41-byte passwords in the `user` table, not 45-byte passwords as in 4.1.0. Any 45-byte passwords created for 4.1.0 must be reset after running the `mysql_fix_privilege_tables` script.

- Added `secure_auth` global server system variable and `--secure-auth` server option that disallow authentication for accounts that have old (pre-4.1.1) passwords.

- Added `--secure-auth` option to `mysql` command-line client. If this option is set, the client refuses to send passwords in old (pre-4.1.1) format.

- Warning: Incompatible change! Renamed the C API `mysql_prepare_result()` function to `mysql_get_metadata()` as the old name was confusing.

- Added `DROP USER 'user_name'@'host_name'` statement to drop an account that has no privileges.

- The interface to aggregated `UDF` functions has changed a bit. You must now declare a `xxx_clear()` function for each aggregate function `XXX()`.

- Added new `ADDTIME()`, `DATE()`, `DATEDIFF()`, `LAST_DAY()`, `MAKEDATE()`, `MAKETIME()`, `MICROSECOND()`, `SUBTIME()`, `TIME()`, `TIMEDIFF()`, `TIMESTAMP()`, `UTC_DATE()`, `UTC_TIME()`, `UTC_TIMESTAMP()`, and `WEEKOFYEAR()` functions.

- Added new syntax for `ADDDATE()` and `SUBDATE()`. The second argument now may be a number representing the number of days to be added to or subtracted from the first date argument.

- Added new `type` values `DAY_MICROSECOND`, `HOUR_MICROSECOND`, `MINUTE_MICROSECOND`, `SECOND_MICROSECOND`, and `MICROSECOND` for `DATE_ADD()`, `DATE_SUB()`, and `EXTRACT()`.

- Added new `%f` microseconds format specifier for `DATE_FORMAT()` and `TIME_FORMAT()`.

- All queries in which at least one `SELECT` does not use indexes properly now are written to the slow query log when long log format is used.

- It is now possible to create a `MERGE` table from `MyISAM` tables in different databases. Formerly, all the `MyISAM` tables had to be in the same database, and the `MERGE` table had to be created in that database as well.

- Added new `COMPRESS()`, `UNCOMPRESS()`, and `UNCOMPRESSED_LENGTH()` functions.

- When using `SET sql_mode='mode'` for a complex mode (like `ANSI`), we now update the `sql_mode` variable to include all the individual options implied by the complex mode.

- Added the OLAP (On-Line Analytical Processing) function `ROLLUP`, which provides summary rows for each `GROUP BY` level.

- Added `SQLSTATE` codes for all server errors.

- Added `mysql_sqlstate()` and `mysql_stmt_sqlstate()` C API client functions that return the `SQLSTATE` error code for the last error.

- `TIME` columns with hour values greater than 24 were returned incorrectly to the client.

- `ANALYZE TABLE`, `OPTIMIZE TABLE`, `REPAIR TABLE`, and `FLUSH` statements are now stored in the binary log and thus replicated to slaves. This logging does not occur if the optional `NO_WRITE_TO_BINLOG` keyword (or its alias `LOCAL`) is given. Exceptions are that `FLUSH LOGS`, `FLUSH MASTER`, `FLUSH SLAVE`, and `FLUSH TABLES WITH READ LOCK` are not logged in any case. For a syntax example, see Section 13.5.4.2, « Syntaxe de `FLUSH` ».

- New global system variable `relay_log_purge` to enable or disable automatic relay log purging.

- `LOAD DATA` now produces warnings that can be fetched with `SHOW WARNINGS`.

- Added support for syntax `CREATE TABLE table2 (LIKE table1)` that creates an empty table `table2` with a definition that is exactly the same as `table1`, including any indexes.

- `CREATE TABLE tbl_name (...) TYPE=storage_engine` now generates a warning if the named storage engine is not available. The table is still created as a `MyISAM` table, as before.

- Most subqueries are now much faster than before.

- Added `PURGE BINARY LOGS` as an alias for `PURGE MASTER LOGS`.

- Disabled the `PURGE LOGS` statement that was added in version 4.1.0. The statement now should be issued as `PURGE MASTER LOGS` or `PURGE BINARY LOGS`.

- Added `SHOW BDB LOGS` as an alias for `SHOW LOGS`.

- Added `SHOW MASTER LOGS` (which had been deleted in version 4.1.0) as an alias for `SHOW BINARY LOGS`.

- Added `Slave_IO_State` and `Seconds_Behind_Master` columns to the output of `SHOW SLAVE STATUS`. `Slave_IO_State` indicates the state of the slave I/O thread, and `Seconds_Behind_Master` indicates the number of seconds by which the slave is late compared to the master.

- The `--lower-case-table-names=1` server option now also makes aliases case insensitive. (Bug#534)

- Changed that the relay log is flushed to disk by the slave I/O thread every time it reads a relay log event. This reduces the risk of losing some part of the relay log in case of brutal crash.

Bogues corrigés :

- Fixed `mysql` parser not to erroneously interpret ‘`;`’ character within `/* ... */` comment as statement terminator.

- Fixed merging types and length of result set columns for `UNION` operations. The types and lengths now are determined taking into account values for all `SELECT` statements in the `UNION`, not just the first `SELECT`.

- Fixed a bug in privilege handling that caused connections from certain IP addresses to be assigned incorrect database-level privileges. A connection could be assigned the database privileges of the previous successful authentication from one of those IP addresses, even if the IP address username and database name were different. (Bug#1636)

- Error-handling functions were not called properly when an error resulted from `[CREATE | REPLACE| INSERT] ... SELECT` statements.

- `HASH`, `BTREE`, `RTREE`, `ERRORS`, and `WARNINGS` no longer are reserved words. (Bug#724)

- Fix for bug in `ROLLUP` when all tables were `const` tables. (Bug#714)

- Fixed a bug in `UNION` that prohibited `NULL` values from being inserted into result set columns where the first `SELECT` of the `UNION` retrieved `NOT NULL` columns. The type and max_length of the result column is now defined based on all `UNION` parts.

- Fixed name resolution of columns of reduced subqueries in unions. (Bug#745)

- Fixed memory overrun in subqueries in select list with `WHERE` clause bigger than outer query `WHERE` clause. (Bug#726)

- Fixed a bug that caused `MyISAM` tables with `FULLTEXT` indexes created in 4.0.x to be unreadable in 4.1.x.

- Fixed a data loss bug in `REPAIR TABLE ... USE_FRM` when used with tables that contained `TIMESTAMP` columns and were created in 4.0.x.

- Fixed reduced subquery processing in `ORDER BY`/`GROUP BY` clauses. (Bug#442)

- Fixed name resolution of outer columns of subquery in `INSERT`/`REPLACE` statements. (Bug#446)

- Fixed bug in marking columns of reduced subqueries. (Bug#679)

- Fixed a bug that made `CREATE FULLTEXT INDEX` syntax illegal.

- Fixed a crash when a `SELECT` that required a temporary table (marked by `Using temporary` in `EXPLAIN` output) was used as a derived table in `EXPLAIN` command. (Bug#251)

- Fixed a rare table corruption bug in `DELETE` from a big table with a new (created by MySQL-4.1) full-text index.

- `LAST_INSERT_ID()` now returns 0 if the last `INSERT` statement didn't insert any rows.

- Fixed missing last character in function output. (Bug#447)

- Fixed a rare replication bug when a transaction spanned two or more relay logs, and the slave was stopped while executing the part of the transaction that was in the second or later relay log. Then replication would resume at the beginning of the second or later relay log, which was incorrect. (It should resume at `BEGIN`, in the first relay log.) (Bug#53)

- `CONNECTION_ID()` now is properly replicated. (Bug#177)

- The new `PASSWORD()` function in 4.1 is now properly replicated. (Bug#344)

- Fixed a bug with double freed memory.

- Fixed a crashing bug in `UNION` operations that involved temporary tables.

- Fixed a crashing bug in `DERIVED TABLES` when `EXPLAIN` is used on a `DERIVED TABLES` with a join.

- Fixed a crashing bug in `DELETE` with `ORDER BY` and `LIMIT` caused by an uninitialized array of reference pointers.

- Fixed a bug in the `USER()` function caused by an error in the size of the allocated string.

- Fixed a crashing bug when attempting to create a table containing a spatial (GIS) column with a storage engine that does not support spatial types.

- Fixed a crashing bug in `UNION` caused by the empty select list and a non-existent column being used in some of the individual `SELECT` statements.

- Fixed a replication bug with a 3.23 master and a 4.0 slave: The slave lost the replicated temporary tables if `FLUSH LOGS` was issued on the master. (Bug#254)

- Fixed a security bug: A server compiled without SSL support still allowed connections by users who had the `REQUIRE SSL` option specified for their accounts.

- When an undefined user variable was used in a updating query on the master (such as `INSERT INTO t VALUES(@a)`, where `@a` had never been set by this connection before), the slave could replicate the query incorrectly if a previous transaction on the master used a user variable of the same name. (Bug#1331)

- Fixed bug with prepared statements: Using the `?` prepared statement parameter as the argument to certain functions or statement clauses caused a server crash when `mysql_prepare()` was invoked. (Bug#1500)

- Fixed bug with prepared statements: after call to mysql_prepare placeholders became allowed in all consequent statements, even if they are not prepared (Bug#1946)

- `SLAVE START` (which is a deprecated syntax, `START SLAVE` should be used instead) could crash the slave. (Bug#2516)

- Fixed bug in `ALTER TABLE RENAME`, when rename to the table with the same name in another database silently dropped destination table if it existed. (Bug#2628)

### C.2.13. Changements de la version 4.1.0 (03 Avril 2003 : alpha)

Fonctionnalité ajoutée ou modifiée :

- Added `--compatible` option to `mysqldump` for producing output that is compatible with other database systems or with older MySQL servers.

- The `--opt` option for `mysqldump` now is enabled by default, as are all the options implied by `--opt`.

- New `CHARSET()` and `COLLATION()` functions to return the character set and collation of a string.

- Allow index type to be specified explicitly for some storage engines via `USING type_name` syntax in index definition.

- New function `IS_USED_LOCK()` for determining the connection identifier of the client that holds a given advisory lock.

- New more secure client authentication based on 45-byte passwords in the `user` table.

- New `CRC32()` function to compute cyclic redundancy check value.

- On Windows, we are now using shared memory to communicate between server and client when they are running on the same machine and you are connecting to `localhost`.

- `REPAIR TABLE` of `MyISAM` tables now uses less temporary disk space when sorting char columns.

- `DATE`/`DATETIME` checking is now a bit stricter to support the ability to automatically distinguish between date, datetime, and time with microseconds. For example, dates of type `YYYYMMDD HHMMDD` are no longer supported; you must either have separators between each `DATE`/`TIME` part or not at all.

- Server side help for all MySQL functions. One can now type `help week` in the `mysql` client and get help for the `week()` function.

- Added new `mysql_get_server_version()` C API client function.

- Fixed bug in `libmysqlclient` that fetched column defaults.

- Fixed bug in `mysql` command-line client in interpreting quotes within comments. (Bug#539)

- Added `record_in_range()` method to `MERGE` tables to be able to choose the right index when there are many to choose from.

- Replication now works with `RAND()` and user variables `@var`.

- Allow one to change mode for `ANSI_QUOTES` on the fly.

- `EXPLAIN SELECT` now can be killed. See Section 13.5.4.3, « Syntaxe de `KILL` ».

- `REPAIR TABLE` now can be killed. See Section 13.5.4.3, « Syntaxe de `KILL` ».

- Allow empty index lists to be specified for `USE INDEX`, `IGNORE INDEX`, and `FORCE INDEX`.

- `DROP TEMPORARY TABLE` now drops only temporary tables and doesn't end transactions.

- Added support for `UNION` in derived tables.

- Warning: Incompatible change! `TIMESTAMP` is now returned as a string of type `'YYYY-MM-DD HH:MM:SS'` and different timestamp lengths are not supported.

  This change was necessary for SQL standards compliance. In a future version, a further change will be made (backward compatible with this change), allowing the timestamp length to indicate the desired number of digits of fractions of a second.

- New faster client/server protocol that supports prepared statements, bound parameters, and bound result columns, binary transfer of data, warnings.

- Added database and real table name (in case of alias) to the `MYSQL_FIELD` structure.

- Multi-line queries: You can now issue several queries at once and then read the results in one go.

- In `CREATE TABLE foo (a INT not null primary key)` the `PRIMARY` word is now optional.

- In `CREATE TABLE` the attribute `SERIAL` is now an alias for `BIGINT UNSIGNED NOT NULL AUTO_INCREMENT UNIQUE`.

- `SELECT ... FROM DUAL` is an alias for `SELECT ...`. (To be compatible with some other databases).

- If one creates a too long `CHAR`/`VARCHAR` it's now automatically changed to `TEXT` or `BLOB`; One will get a warning in this case.

- One can specify the different `BLOB`/`TEXT` types with the syntax `BLOB(length)` and `TEXT(length)`. MySQL will automatically change it to one of the internal `BLOB`/`TEXT` types.

- `CHAR BYTE` is an alias for `CHAR BINARY`.

- `VARCHARACTER` is an alias for `VARCHAR`.

- New operators `integer MOD integer` and `integer DIV integer`.

- `SERIAL DEFAULT VALUE` added as an alias for `AUTO_INCREMENT`.

- `TRUE` and `FALSE` added as alias for 1 and 0, respectively.

- Aliases are now forced in derived tables, as per standard SQL.

- Fixed `SELECT .. LIMIT 0` to return proper row count for `SQL_CALC_FOUND_ROWS`.

- One can specify many temporary directories to be used in a round-robin fashion with: `--tmpdir=dirname1:dirname2:dirname3`.

- Subqueries: `SELECT * from t1 where t1.a=(SELECT t2.b FROM t2)`.

- Derived tables:

      SELECT a.col1, b.col2
             FROM (SELECT MAX(col1) AS col1 FROM root_table) a,
             other_table b
             WHERE a.col1=b.col1;

- Character sets to be defined per column, table and database.

- Unicode (UTF8) support.

- New `CONVERT(... USING ...)` syntax for converting string values between character sets.

- `BTREE` index on `MEMORY` (`HEAP`) tables.

- Faster embedded server (new internal communication protocol).

- One can add a comment per column in `CREATE TABLE`.

- `SHOW FULL COLUMNS FROM tbl_name` shows column comments.

- `ALTER DATABASE`.

- Support for GIS (Geometrical data). See Chapitre 18, Données spatiales avec MySQL.

- `SHOW [COUNT(*)] WARNINGS` shows warnings from the last command.

- One can specify a column type for a column in `CREATE TABLE ... SELECT` by defining the column in the `CREATE` part.

      CREATE TABLE foo (a TINYINT NOT NULL) SELECT b+1 AS a FROM bar;

- `expr SOUNDS LIKE expr` same as `SOUNDEX(expr)=SOUNDEX(expr)`.

- Added new `VARIANCE(expr)` function returns the variance of `expr`

- One can create a table from the existing table using `CREATE [TEMPORARY] TABLE [IF NOT EXISTS] table (LIKE table)`. The table can be either normal or temporary.

- New options `--reconnect` and `--skip-reconnect` for the `mysql` client, to reconnect automatically or not if the connection is lost.

- `START SLAVE` (`STOP SLAVE`) no longer returns an error if the slave is already started (stopped); it returns a warning instead.

- `SLAVE START` and `SLAVE STOP` are no longer accepted by the query parser; use `START SLAVE` and `STOP SLAVE` instead.

## C.3. Changements de la version 4.0.x (Production)

Version 4.0 of the MySQL server includes many enhancements and new features:

- The `InnoDB` storage engine is now included in the standard binaries, adding transactions, row-level locking, and foreign keys. See Chapitre 15, Le moteur de tables `InnoDB`.

- A query cache, offering vastly increased performance for many applications. By caching complete result sets, later identical queries can return instantly. See Section 5.11, « Cache de requêtes MySQL ».

- Improved full-text indexing with boolean mode, truncation, and phrase searching. See Section 12.6, « Recherche en texte intégral (`Full-text`) dans MySQL ».

- Enhanced `MERGE` tables, now supporting `INSERT` statements and `AUTO_INCREMENT`. See Section 14.2, « Tables assemblées `MERGE` ».

- `UNION` syntax in `SELECT`. See Section 13.1.7.2, « Syntaxe de `UNION` ».

- Multiple-table `DELETE` statements. See Section 13.1.1, « Syntaxe de `DELETE` ».

- `libmysqld`, the embedded server library. See Section 24.2.16, « `libmysqld`, la bibliothèque du serveur embarqué MySQL ».

- Additional `GRANT` privilege options for even tighter control and security. See Section 13.5.1.3, « Syntaxe de `GRANT` et `REVOKE` ».

- Management of user resources in the `GRANT` system, particularly useful for ISPs and other hosting providers. See Section 5.6.4, « Limiter les ressources utilisateurs ».

- Dynamic server variables, allowing configuration changes to be made without having to stop and restart the server. See Section 13.5.2.8, « Syntaxe de `SET` ».

- Improved replication code and features. See Chapitre 6, Réplication de MySQL.

- Numerous new functions and options.

- Changes to existing code for enhanced performance and reliability.

For a full list of changes, please refer to the changelog sections for each individual 4.0.x release.

### C.3.1. Changements de la version 4.0.25 (pas encore publié)

Fonctionnalité ajoutée ou modifiée :

- Added `--with-big-tables` compilation option to configure. (Previously it was necessary to pass `-DBIG_TABLES` to the compiler manually in order to enable large table support.) Section 2.4.2, « Options habituelles de `configure` » for details.

Bogues corrigés :

- Fixed a deadlock resulting from use of `FLUSH TABLES WITH READ LOCK` while an `INSERT DELAYED` statement is in progress. (Bug#7823)

- Fixed a segmentation fault in mysqlcheck that occurred when the last table checked in `--auto-repair` mode returned an error (such as the table being a `MERGE` table). (Bug#9492)

- Fixed faulty display of `TIMESTAMP` columns retrieved as ``col_name`+0` while the `new` system variable is set to 1. (Bug#8894)

- Queries containing `CURRENT_USER()` incorrectly were registered in the query cache. (Bug#9796)

- Fixed problems with static variables to allow building on Fedora Core 3. (Bug#6554)

- An `UPDATE` that updated only some of the columns in a multiple-column index could result in a loop. (Bug#8942)

- `REPAIR TABLE` did not invalidate query results in the query cache that were generated from the table. (Bug#8480)

- Fixed a bug that caused concurrent inserts to be allowed into the tables in the `SELECT ... UNION ...` part of `INSERT ... SELECT ... UNION ...`. This could result in the incorrect order of queries in the binary log. (Bug#9922)

- Fixed a bug that under certain circumstances could allow a privilege escalation via database wildcards in `GRANT`. (Bug#3924, CAN-2004-0957)

- `<=>` was not properly comparing `NULL` values in the `WHERE` clause of outer joins. (Bug#8711)

- InnoDB: Fixed a bug : MySQL-4.0.23 and 4.0.24 could complain that an InnoDB table created with MySQL-3.23.49 or earlier was in the new compact InnoDB table format of 5.0.3 or later, and InnoDB would refuse to use that table. (The same bug exists in 4.1.8 - 4.1.10.) There is nothing wrong with the table, it is mysqld that is in error. Workaround: wait that 4.0.25 or 4.1.11 is released before doing an upgrade, or dump the table and recreate it with any MySQL version >= 3.23.50 before upgrading to 4.0.23 or 4.0.24.

### C.3.2. Changements de la version 4.0.24 (04 Mars 2005)

Fonctionnalité ajoutée ou modifiée :

- Security improvement: The server creates `.frm`, `.MYD`, `.MYI`, `.MRG`, `.ISD`, and `.ISM` table files only if a file with the same name does not already exist. Thanks to Stefano Di Paola `<stefano.dipaola@wisec.it>` for finding and informing us about this issue. (CAN-2005-0711)

- Security improvement: User-defined functions should have at least one symbol defined in addition to the `xxx` symbol that corresponds to the main `xxx()` function. These auxiliary symbols correspond to the `xxx_init()`, `xxx_deinit()`, `xxx_reset()`, `xxx_clear()`, and `xxx_add()` functions. mysqld by default no longer loads UDFs unless they have at least one auxiliary symbol defined in addition to the main symbol. The `--allow-suspicious-udfs` option controls whether UDFs that have only an `xxx` symbol can be loaded. By default, the option is off. `mysqld` also checks UDF filenames when it reads them from the `mysql.func` table and rejects those that contain directory pathname separator characters. (It already checked names as given in `CREATE FUNCTION` statements.) See Section 27.2.3.1, « Fonctions utilisateur : appeler des fonctions simples », Section 27.2.3.2, « Appeler des fonctions utilisateurs pour les groupements », and Section 27.2.3.6, « Précautions à prendre avec les fonctions utilisateur ». Thanks to Stefano Di Paola `<stefano.dipaola@wisec.it>` for finding and informing us about this issue. (CAN-2005-0709, CAN-2005-0710)

- `InnoDB`: Added configuration option and settable global variable `innodb_autoextend_increment` for setting the size in megabytes by which `InnoDB` tablespaces are extended when they become full. The default value is 8, corresponding to the fixed increment of 8MB in previous versions of MySQL.

- InnoDB: Do not acquire an internal `InnoDB` table lock in `LOCK TABLES` if `AUTOCOMMIT=1`. This helps in porting old `MyISAM` applications to `InnoDB`. `InnoDB` table locks in that case caused deadlocks very easily.

Bogues corrigés :

- `AES_DECRYPT(`col_name`,`key`)` could fail to return `NULL` for invalid values in `col_name`, if `col_name` was declared as `NOT NULL`. (Bug#8669)

- `FOUND_ROWS()` returned an incorrect value after a `SELECT SQL_CALC_FOUND_ROWS DISTINCT` statement that selected constants and included `GROUP BY` and `LIMIT` clauses. (Bug#7945)

- Queries of the form `(SELECT ...) ORDER BY ...` were being treated as a `UNION`. This improperly resulted in only distinct values being returned (because `UNION` by default eliminates.) (Bug#7672)

- Index cardinality was not being updated properly for `TEMPORARY` tables under some circumstances, such as `CREATE TABLE ... SELECT` followed by `ANALYZE TABLE`. (Bug#7519)

- Fixed a server crash caused by `DELETE FROM `tbl_name` ... WHERE ... ORDER BY `tbl_name`.`col_name`` when the `ORDER BY` column was qualified with the table name. (Bug#8392)

- Fixed a bug in `MATCH ... AGAINST` in natural language mode that could cause a server crash if the `FULLTEXT` index was not used in a join (`EXPLAIN` did not show `fulltext` join mode) and the search query matched no rows in the table (Bug#8522).

- Platform and architecture information in version information produced for `--version` option on Windows was always `Win95/Win98 (i32)`. More accurately determine platform as `Win32` or `Win64` for 32-bit or 64-bit Windows, and architecture as `ia32` for x86, `ia64` for Itanium, and `axp` for Alpha. (Bug#4445)

- Fixed an optimization problem that allowed a negative number to be stored in a `DOUBLE UNSIGNED` column when it was assigned a value from a signed `DOUBLE` column. (Bug#7700)

- Fixed a failure of multiple-table updates to replicate properly on slave servers when `--replicate-*-table` options had been specified. (Bug#7011)

- Renamed `set_bit()` and `clear_bit()` functions in source code to avoid a conflict with functions of the same names in Linux kernel header files. (Bug#7971)

- Part of the information being used to cache access-permission lookups was not always reinitialized properly, particularly for connections from localhost on Windows. The result was connection failures that appeared to occur randomly. (Bug#5569)

- Corrected a problem with the `QUOTE()` function returning bad results. (Bug#8248)

- Fixed a problem where `INSERT INTO ...SELECT` failed when the source and target table were the same. (Bug#6034)

- Fixed a problem where RPM installation on Linux as a non-privileged user would result in incomplete installation. (Bug#7347)

- Change thread stack size used for building Linux RPM distributions to avoid warnings about stack size during server startup. (Bug#6226)

- Fixed a symlink vulnerability in the mysqlaccess script. Reported by Javier Fernandez-Sanguino Pena and Debian Security Audit Team. (CAN-2005-0004)

- Fixed support for C API function `mysql_list_fields()`, which was accidentally broken in 4.0.22 (Bug#6761)

- Make `query_cache_wlock_invalidate` system variable visible in `SHOW VARIABLES` output. (Bug#7594)

- Fixed a bug which caused `FROM_UNIXTIME()` function to return `NULL` for zero argument instead of the Epoch. (Bug#7515)

- Now in datetime values two digit year is interpreted as year in 20th or 21st century even with zero month and day. (Bug#7297)

- Fixed a bug in `QUOTE` function when used in conjunction with some other string functions. This lead to severe buffer overflow and server crashing. (Bug#7495)

- InnoDB: Work around a problem in AIX 5.1 patched with ML7 security patch: InnoDB would refuse to open its `ibdata` files, complaining about an operating system error 0.

- InnoDB: Fixed a memory corruption bug if one created a table with a primary key that contained at least two column prefixes. An example: `CREATE TABLE t(a char(100), b tinyblob, PRIMARY KEY(a(5), b(10)))`.

- InnoDB: Use native `tmpfile()` function on Netware. All InnoDB temporary files are created under `sys:\tmp`. Previously, InnoDB temporary files were never deleted on Netware.

- `InnoDB`: Honor the `--tmpdir` startup option when creating temporary files. Previously, `InnoDB` temporary files were always created in the temporary directory of the operating system. On Netware, `InnoDB` will continue to ignore `--tmpdir`. (Bug#5822)

- InnoDB: Fix a theoretical hang over the adaptive hash latch in InnoDB if one runs `INSERT ... SELECT ...` (binlog not enabled), or a multi-table `UPDATE` or `DELETE`, and only the read tables are InnoDB type, the rest are MyISAM; this also fixes Bug#7879 for InnoDB type tables. (Bug#7879)

- InnoDB: Fixed a bug : 32-bit mysqld binaries built on HP-UX-11 did not work with `InnoDB` files greater than 2 GB in size. (Bug#6189)

- InnoDB: Fixed a bug : InnoDB failed to drop a table in the background drop queue if the table was referenced by a foreign key constraint.

- InnoDB: Fixed a bug : if we dropped a table where an `INSERT` was waiting for a lock to check a `FOREIGN KEY` constraint, then an assertion would fail in `lock_reset_all_on_table()`, since that operation assumes no waiting locks on the table or its records.

- Fixed that, when encountering a ``disk full'' or ``quota exceeded'' write error, `MyISAM` sometimes didn't sleep and retry the write, thus resulting in a corrupted table. (Bug#7714)

- Fixed that a slave could crash after replicating many `ANALYZE TABLE`, `OPTIMIZE TABLE`, or `REPAIR TABLE` statements from the master. (Bug#6461, Bug#7658)

- Fixed a bug where MySQL was allowing concurrent updates (inserts, deletes) to a table if binary logging is enabled. Changed to ensure that all updates are executed in a serialized fashion, because they are executed serialized when binlog is replayed. (Bug#7879)

- Fixed a bug that caused the slave to stop on statements that produced an error on the master. (Bug#8412)

- Documented problem with using `mysqldump` in 4.0.x to dump `TIMESTAMP(2)` and `TIMESTAMP(4)` column types. (Bug#6530)

### C.3.3. Changements de la version 4.0.23 (18 Décembre 2004)

Note: Due to a libtool-related bug in the source distribution, the creation of shared `libmysqlclient` libraries was not possible (the resulting files were missing the `.so` file name extension). The file `ltmain.sh` was updated to fix this problem and the resulting source distribution was released as `mysql-4.0.23a.tar.gz`. This modification did not affect the binary packages. (Bug#7401)

Fonctionnalité ajoutée ou modifiée :

- Added `--hex-blob` option to mysqldump for dumping binary string columns using hexadecimal notation.

- Added `mysql_hex_string()` C API function that hex-encodes a string.

- InnoDB: Do not periodically write `SHOW INNODB STATUS` information to a temporary file unless the configuration option `innodb_status_file=1` is set.

- InnoDB: Made the foreign key parser better aware of quotes. (Bug#6340)

- `mysqlbinlog` now prints an informative commented line (thread id, timestamp, server id, etc) before each `LOAD DATA INFILE`, like it does for other queries; unless `--short-form` is used.

Bogues corrigés :

- Corrected accounts in the `mysql.user` table in Windows distributions that had been created with a `Host` value of `build` rather than `%`. (Bug#6000)

- Prevent adding `CREATE TABLE .. SELECT` query to the binary log when the insertion of new records partially failed. (Bug#6682)

- Fixed bug which caused `FROM_UNIXTIME()` function to return wrong result if the argument was too big. (Bug#6439)

- Fixed bug which caused MySQL server to store wrong values in `TIMESTAMP` columns and give wrong results for `UNIX_TIMESTAMP()` function if it was run in time zone with leap seconds. (Bug#6387)

- InnoDB: Fixed a bug in `LOAD DATA INFILE…REPLACE` printing duplicate key error when executing the same load query several times. (Bug#5835)

- InnoDB: Refuse to open new-style tables created with MySQL 5.0.3 or later. (Bug#7089)

- InnoDB: Do not call `rewind()` when displaying `SHOW INNODB STATUS` information on `stderr`.

- InnoDB: If one used `INSERT IGNORE` to insert several rows at a time, and the first inserts were ignored because of a duplicate key collision, then InnoDB in a replication slave assigned `AUTO_INCREMENT` values 1 bigger than in the master. This broke the MySQL replication. (Bug#6287)

- InnoDB: Fix two hangs: `FOREIGN KEY` constraints treated table and database names as case-insensitive. `RENAME TABLE t TO T` would hang in an endless loop if `t` had a foreign key constraint defined on it. Fix also a hang over the dictionary mutex that would occur if one tried in `ALTER TABLE` or `RENAME TABLE` to create a foreign key constraint name that collided with another existing name. (Bug#3478)

- InnoDB: Treat character `0xA0` as space in InnoDB's `FOREIGN KEY` parser if MySQL treats it as space in the default charset. EMS MySQL Manager inserts character `0xA0` after the table name in an `ALTER`, which confused InnoDB's parser.

- Fixed a bug which caused a crash when only the slave I/O thread was stopped and restarted. (Bug#6148)

- If a connection had an open transaction but had done no updates to transactional tables (for example if had just done a `SELECT FOR UPDATE` then executed a non-transactional update, that update automatically committed the transaction (thus releasing InnoDB's row-level locks etc). (Bug#5714)

- If a connection was interrupted by a network error and did a rollback, the network error code got stored into the `BEGIN` and `ROLLBACK` binary log events; that caused superfluous slave stops. (Bug#6522)

- A sequence of `BEGIN` (or `SET AUTOCOMMIT=0`), `FLUSH TABLES WITH READ LOCK`, transactional update, `COMMIT`, `FLUSH TABLES WITH READ LOCK` could hang the connection forever and possibly the MySQL server itself. This happened for example when running the `innobackup` script several times. (Bug#6732)

### C.3.4. Changements de la version 4.0.22 (27 Octobre 2004)

Fonctionnalités ajoutées ou modifiées :

- InnoDB: Made `LOCK TABLES` behave by default like it did before MySQL 4.0.20 or 4.1.2: no `InnoDB` lock will be taken. Added a startup option and settable system variable `innodb_table_locks` for making `LOCK TABLE` acquire also `InnoDB` locks. See Section 15.17, « Restrictions sur les tables `InnoDB` ». (Bug#3299, Bug#5998)

- The `--with-openssl` option for configure now accepts a path prefix as an argument. `--with-openssl-includes` and `--with-openssl-libs` still are supported, but are needed only to override the default values. (Bug#5494)

- Added new `--without-man` option to configure to suppress building/installing the manual pages. (Bug#5379)

Bogues corrigés :

- Fixed bug in server which caused connection stall when one of deprecated `libmysqlclient` functions `mysql_create_db(), mysql_rm_db()` were called and were going to return error. (Bug#6081)

- Fixed returning wrong query result from query cache if temporary table haded real tables after putting results to query cache. (Bug#6084)

- Fixed `ENABLE KEYS`, which failed if `tmpdir` ran out of space. Now, a full repair is done in this case. (Bug#5625)

- Fixed an improper error message when trying to drop a table which is referenced by a `FOREIGN KEY` constraint. (Bug#5784)

- Fixed a bug that allowed `FLUSH TABLE(S)` to close `HANDLER` tables. `HANDLER` tables now are re-opened after a `FLUSH TABLE(S)` when they are next used. However, they lose their file position if this happens. (Bug#4286)

- Fixed a bug that allowed `HANDLER` tables with the same alias to be multiple opened. `HANDLER` aliases must now be unique, even though it is syntactically correct in versions below 4.1, to qualify them with their base table's database name (e.g. test_db.handler_tbl, but this will now conflict with e.g. another_db.handler_tbl). (Bug#4335)

- Fixed crash when using MySQL 4.0 with privilege tables from MySQL 5.0.

- InnoDB: Make the check for excessive semaphore waits tolerate glitches in the system clock (do not crash the server if the system time is adjusted while InnoDB is under load.). (Bug#5898)

- mysqlimport now reads input files locally from the client host only if the `--local` option is given. Previously, it assumed incorrectly in some cases that files were local even without `--local`. (Bug#5829)

- InnoDB: Fixed a bug in the InnoDB `FOREIGN KEY` parser that prevented `ALTER TABLE` of tables containing ‘`#`’ in their names. (Bug#5856)

- Fixed a bug which resulted in erronously calculated number of examined rows in `UNION`'s. This value is printed in the slow query log. (Bug#5879)

- Fixed bug with crash of server on some values of read_rnd_buffer_size (Bug#5492)

- Fixed bug which caused truncation of values read from or into `TIMESTAMP` fields if `--new` mode was enabled. (Bug#4131)

- mysqladmin now returns a status of 0 even when the server denies access; such an error means theserver is running. (Bug#3120)

- InnoDB: Fixed a bug introduced in 4.0.21. An assertion failed if one used mysqldump with the option `-l` or `--opt`, or if one used `LOCK TABLES ... LOCAL`. (Workaround in 4.0.21: use `--quick` and `--single-transaction`. (Bug#5538)

- Fixed that if the slave SQL thread found a syntax error in a query (which should be rare, as the master parsed it successfully), it stops. (Bug#5711)

- Fixed that if a write to a MyISAM table fails because of a full disk or an exceeded disk quota, it prints a message to the error log every 10 minutes, and waits until disk becomes free. (Bug#3248)

- Fixed problem with symlinked databases on Windows being shown with `SHOW DATABASES` even if the database name doesn't match the given wildcard (Bug#5539)

- Fixed problem introduced in 4.0.21 where a connection starting a transaction, doing updates, then `FLUSH TABLES WITH READ LOCK`, then `COMMIT`, would cause replication slaves to stop complaing about error 1223. Bug surfaced when using the InnoDB `innobackup` script. (Bug#5949)

### C.3.5. Changements de la version 4.0.21

Fonctionnalité ajoutée ou modifiée :

Bogues corrigés :

- Fixed a bug with truncation of big values (> 4294967295) of 64-bit system variables. (Bug#3754)

### C.3.6. Changements de la version 4.0.20

Fonctionnalité ajoutée ou modifiée :

- Phrase search in `MATCH ... AGAINST ( ... IN BOOLEAN MODE)` no longer matches partial words.

Bogues corrigés :

- Fixed a bug in division `/` reporting incorrect metadata (number of digits after the decimal point). It can be seen, e.g. in `CREATE TABLE t1 SELECT "0.01"/"3"`. (Bug#3612)

- Fixed a problem with non-working `DROP DATABASE` on some configurations (in particular, Linux 2.6.5 with ext3 are known to expose this bug). (Bug#3594)

- Fixed that in some replication error messages, a very long query caused the rest of the message to be invisible (truncated), by putting the query last in the message. (Bug#3357)

### C.3.7. Changements de la version 4.0.19 (04 mai 2004)

Note: The MySQL 4.0.19 binaries were uploaded to the download mirrors on May, 10th. However, a potential crashing bug was found just before the 4.0.19 release was publicly announced and published from the 4.0 download pages at http://dev.mysql.com/.

See (Bug#3596) for details (it was reported against MySQL-4.1, but was confirmed to affect 4.0.19 as well).

A fix for this bug was pushed into the MySQL source tree shortly after it could be reproduced and will be included in the upcoming MySQL 4.0.20, to be released shortly. We recommend users to stick to MySQL 4.0.18 for the time being, until MySQL 4.0.20 has been released (this specific bug was introduced after MySQL 4.0.18 was released, so older versions were not affected by it). We apologize for the inconvenience!

Fonctionnalité ajoutée ou modifiée :

- If length of a timestamp field is defined as 19, the timestamp will be displayed as `"YYYY-MM-DD HH:MM:SS`. This is done to make it easier to use tables created in MySQL 4.1 to be used in MySQL 4.0.

- If you use `RAID_CHUNKS` with a value > 255 it will be set to 255. This was made to ensure that all raid directories are always 2 hex bytes. (Bug#3182)

- Changed that the optimizer will now consider the index specified in `FORCE INDEX` clause as a candidate to resolve `ORDER BY` as well.

- Non-standard behavior of `UNION` statements has changed to the standard ones. So far, a table name in the `ORDER BY` clause was tolerated. From now on a proper error message is issued (Bug#3064).

- Added `max_insert_delayed_threads` system variable as a synonym for `max_delayed_threads`.

- Added `query_cache_wlock_invalidate` system variable. It allow emulation of `MyISAM` table write-locking behavior, even for queries in the query cache. (Bug#2693)

- The keyword `MASTER_SERVER_ID` is not reserved anymore.

- The following is mainly relevant for Mac OS X users who use a case-insensitive filesystem. This is not relevant for Windows users as `InnoDB` in this case always stores file names in lower case:

  One can now force `lower_case_table_names` to 0 from the command line or a configuration file. This is useful with case-insensitive filesystems when you have previously not used `lower_case_table_names=1` or `lower_case_table_names=2` and your have already created `InnoDB` tables. With `lower_case_table_names=0`, `InnoDB` tables were stored in mixed case while setting lower_case_table_names <> 0 will now force it to lower case (to make the table names case insensitive).

  Because it's possible to crash `MyISAM` tables by referring to them with different case on a case-insensitive filesystem, we recommend that you use `lower_case_table_names` or `lower_case_table_names=2` on such filesystems.

  The easiest way to convert to use `lower_case_table_names=2` is to dump all your `InnoDB` tables with `mysqldump`, drop them and then restore them.

- Non-standard behavior of `UNION` statements has changed to the standard ones. So far, a table name in the `ORDER BY` clause was tolerated. From now on a proper error message is issued (Bug#3064).

- Added `max_insert_delayed_threads` system variable as a synonym for `max_delayed_threads`.

- Added `query_cache_wlock_invalidate` system variable. It allow emulation of `MyISAM` table write-locking behavior, even for queries in the query cache. (Bug#2693)

- Changed that the relay log is flushed to disk by the slave I/O thread every time it reads a relay log event. This reduces the risk of losing some part of the relay log in case of brutal crash.

- When a session having open temporary tables terminates, the statement automatically written to the binary log is now `DROP TEMPORARY TABLE IF EXISTS` instead of `DROP TEMPORARY TABLE`, for more robustness.

- Added option `--replicate-same-server-id`.

Bogues corrigés :

- Added missing full-text variable `ft_stopword_file` to `myisamchk`.

- Don't allow stray `','` at the end of field specifications. (Bug#3481)

- `INTERVAL` now can handle big values for seconds, minutes and hours. (Bug#3498)

- Blank hostname did not work as documented for table and column privileges. Now it's works the same way as `'%'`. (Bug#3473)

- Fixed a harmless buffer overflow in `replace` utility. (Bug# 3541)

- Fixed `SOUNDEX()` to ignore non-alphabetic characters also in the beginning of the string. (Bug#3556)

- Fixed a bug in `MATCH ... AGAINST()` searches when another thread was doing concurrent inserts into the `MyISAM` table in question. The first --- full-text search --- query could return incorrect results in this case (e.g. ``phantom'' rows or not all matching rows, even an empty result set). The easiest way to check whether you are affected is to start `mysqld` with `--skip-concurrent-insert` switch and see if it helps.

- Fixed bug when doing `DROP DATABASE` on a directory containing non- MySQL files. Now a proper error message is returned.

- Fixed bug in `ANALYZE TABLE` on a `BDB` table inside a transaction that hangs server thread. (Bug#2342)

- Fixed a symlink vulnerability in `mysqlbug` script. (Bug#3284)

- Fixed core dump bug in `SELECT DISTINCT` where all selected parts where constants and there were hidden columns in the created temporary table. (Bug#3203)

- Fixed core dump bug in `COUNT(DISTINCT)` when there was a lot of values and one had a big value for `max_heap_table_size`.

- Fixed problem with multi-table-update and BDB tables. (Bug: #3098)

- Fixed memory leak when dropping database with `RAID` tables. (Bug#2882)

- Fixed core dump crash in replication during relay-log switch when the relay log went over `max_relay_log_size` and the slave thread did a `flush_io_cache()` at the same time.

- Fixed hangup bug when issuing multiple `SLAVE START` from different threads at the same time. (Bug#2921)

- Fixed bug when using `DROP DATABASE` with `lower_case_table_names=2`.

- Fixed wrong result in `UNION` when using `lower_case_table_names=2`. (Bug#2858)

- One can now kill threads that is 'stuck' in the join optimizer (can happen when there is MANY tables in the join in which case the optimizer can take really long time). (Bug#2825)

- Rollback `DELETE` and `UPDATE` statements if thread is killed. (Bug#2422)

- Ensure that all rows in an `INSERT DELAYED` statement is written at once if binary logging is enabled. (Bug#2491).

- Fixed bug in query cache statistic, more accurate formula linked statistic variables mentioned in the manual.

- Fixed a bug in parallel repair (`myisamchk -p`, `myisam_repair_threads`) - sometimes repair process failed to repair a table. (Bug#1334)

- Fixed bugs with names of tables, databases and columns that end to space (Bug#2985)

- Fixed a bug in multiple-table `UPDATE` statements involving at least one constant table. Bug was exhibited in allowing non matching row to be updated. (Bug#2996).

- Fixed all bugs in scripts for creating/upgrading system database (Bug#2874) Added tests which guarantee against such bugs in the future.

- Fixed bug in `mysql` command-line client in interpreting quotes within comments. (Bug#539)

- `--set-character-set` and `--character-sets-dir` options in `myisamchk` now work.

- Fixed a bug in `mysqlbinlog` that caused one pointer to be free'd twice in some cases.

- Fixed a bug in boolean full-text search, that sometimes could lead to false matches in queries with several levels of subexpressions using `+` operator (for example, `MATCH ... AGAINST('+(+(word1 word2)) +word3*' IN BOOLEAN MODE)`.

- Fixed Windows-specific portability bugs in `myisam_ftdump`.

- Fixed a bug in multiple-table `DELETE` that was caused by foreign key constraints. If the order of the tables established by MySQL optimizer did not match parent-child order, no rows were deleted and no error message was provided. (Bug#2799)

- Fixed a few years old bug in the range optimizer that caused a segmentation fault on some very rare queries. (Bug#2698)

- Replication: If a client connects to a slave server and issues an administrative statement for a table (for example, `OPTIMIZE TABLE` or `REPAIR TABLE`), this could sometimes stop the slave SQL thread. This does not lead to any corruption, but you must use `START SLAVE` to get replication going again. (Bug#1858) The bug was accidentally not fixed in 4.0.17 as it was unfortunately earlier said.

- Fixed that when a `Rotate` event is found by the slave SQL thread in the middle of a transaction, the value of `Relay_Log_Pos` in `SHOW SLAVE STATUS` remains correct. (Bug#3017)

- Corrected the master's binary log position that `InnoDB` reports when it is doing a crash recovery on a slave server. (Bug#3015)

- Changed that when a `DROP TEMPORARY TABLE` statement is automatically written to the binary log when a session ends, the statement is recorded with an error code of value zero (this ensures that killing a `SELECT` on the master does not result in a superfluous error on the slave). (Bug#3063)

- Changed that when a thread handling `INSERT DELAYED` (also known as a `delayed_insert` thread) is killed, its statements are recorded with an error code of value zero (killing such a thread does not endanger replication, so we thus avoid a superfluous error on the slave). (Bug#3081)

- Fixed deadlock when two `START SLAVE` commands were run at the same time. (Bug#2921)

- Fixed that a statement never triggers a superfluous error on the slave, if it must be excluded given the `replicate-*` options. The bug was that if the statement had been killed on the master, the slave would stop. (Bug#2983)

- The `--local-load` option of `mysqlbinlog` now requires an argument.

- Fixed a segmentation fault when running `LOAD DATA FROM MASTER` after `RESET SLAVE`. (Bug#2922)

- Fixed a rare error condition that caused the slave SQL thread spuriously to print the message `Binlog has bad magic number` and stop when it was not necessary to do so. (Bug#3401)

- Fixed the column `Exec_master_log_pos` (and its disk image in the `relay-log.info` file) to be correct if the master had version 3.23 (it was too big by 6 bytes). This bug does not exist in the 5.0 version. (Bug#3400)

- Fixed that `mysqlbinlog` does not forget to print a `USE` command under rare circumstances where the binary log contained a `LOAD DATA INFILE` command. (Bug#3415)

- Fixed a memory corruption when replicating a `LOAD DATA INFILE` when the master had version 3.23. Some smaller problems remain in this setup, See Section 6.7, « Fonctionnalités de la réplication et problèmes connus ». (Bug#3422)

- Multiple-table `DELETE` statements were always replicated by the slave if there were some `replicate-*-ignore-table` options and no `replicate-*-do-table` options. (Bug#3461)

- Fixed a crash of the MySQL slave server when it was built with `--with-debug` and replicating itself. (Bug#3568)

### C.3.8. Changements de la version 4.0.18 (pas encore publiée)

Fonctionnalité ajoutée ou modifiée :

- Fixed processing of `LOAD DATA` by `mysqlbinlog` in remote mode. (Bug#1378)

- New utility program `myisam_ftdump` was added to binary distributions.

- `ENGINE` is now a synonym for the `TYPE` option for `CREATE TABLE` and `ALTER TABLE`.

- `lower_case_table_names` system variable now can take a value of `2`, to store table names in mixed case on case-insensitive filesystems. It's forced to 2 if the database directory is located on a case-insensitive filesystem.

- For replication of `MEMORY` (`HEAP`) tables: Made the master automatically write a `DELETE FROM` statement to its binary log when a `MEMORY` table is opened for the first time since master's startup. This is for the case where the slave has replicated a non-empty `MEMORY` table, then the master is shut down and restarted: the table is now empty on master; the `DELETE FROM` empties it on slave too. Note that even with this fix, between the master's restart and the first use of the table on master, the slave still has out-of-date data in the table. But if you use the `init-file` option to populate the `MEMORY` table on the master at startup, it ensures that the failing time interval is zero. (Bug#2477)

- Optimizer is now better tuned for the case where the first used key part (of many) is a constant. (Bug#1679)

- Removed old non-working `--old-rpl-compat` server option, which was a holdover from the very first 4.0.x versions. (Bug#2428)

Bogues corrigés :

- `mysqlhotcopy` now works on NetWare.

- `DROP DATABASE` could not drop databases with RAID tables that had more than nine `RAID_CHUNKS`. (Bug#2627)

- Fixed bug in range optimizer when using overlapping ranges. (Bug#2448)

- Limit `wait_timeout` to 2147483 on Windows (OS limit). (Bug#2400)

- Fixed bug when `--init-file` crashes MySQL if it contains a large `SELECT`. (Bug#2526)

- `SHOW KEYS` now shows `NULL` in the `Sub_part` column for `FULLTEXT` indexes.

- The signal thread's stack size was increased to enable `mysqld` to run on Debian/IA-64 with a TLS-enabled `glibc`. (Bug#2599)

- Now only the `SELECT` privilege is needed for tables that are only read in multiple-table `UPDATE` statements. (Bug#2377)

- Give proper error message if one uses `LOCK TABLES ... ; INSERT ... SELECT` and one used the same table in the `INSERT` and `SELECT` part. (Bug#2296)

- `SELECT INTO ... DUMPFILE` now deletes the generated file on error.

- Fixed foreign key reference handling to allow references to column names that contain spaces. (Bug#1725)

- Fixed problem with index reads on character columns with `BDB` tables. The symptom was that data could be returned in the wrong lettercase. (Bug#2509)

- Fixed a spurious table corruption problem that could sometimes appear on tables with indexed `TEXT` columns if these columns happened to contain values having trailing spaces. This bug was introduced in 4.0.17.

- Fixed a problem where some queries could hang if a condition like `indexed_TEXT_column = expr` was present and the column contained values having trailing spaces. This bug was introduced in 4.0.17.

- Fixed a bug that could cause incorrect results from a query that involved range conditions on indexed `TEXT` columns that happened to contain values having trailing spaces. This bug was introduced in 4.0.17. (Bug#2295)

- Fixed incorrect path names in some of the manual pages. (Bug#2270)

- Fixed spurious ``table corrupted'' errors in parallel repair operations. See Section 5.2.3, « Variables serveur système ».

- Fixed a crashing bug in parallel repair operations. See Section 5.2.3, « Variables serveur système ».

- Fixed bug in updating `MyISAM` tables for `BLOB` values longer than 16MB. (Bug#2159)

- Fixed bug in `mysqld_safe` when running multiple instances of MySQL. (Bug#2114)

- Fixed a bug in using `HANDLER` statement with tables not from a current database. (Bug#2304)

- Fixed a crashing bug that occurred due to the fact that multiple-table `UPDATE` statements did not check that there was only one table to be updated. (Bug#2103)

- Fixed a crashing bug that occurred due to `BLOB` column type index size being calculated incorrectly in `MIN()` and `MAX()` optimizations. (Bug#2189)

- Fixed a bug with incorrect syntax for `LOCK TABLES` in `mysqldump`. (Bug#2242)

- Fixed a bug in `mysqld_safe` that caused `mysqld` to generate a warning about duplicate `user=xxx` options if this option was specified in the `[mysqld]` or `[server]` sections of `my.cnf`. (Bug#2163)

- `INSERT DELAYED ... SELECT ...` could cause table corruption because tables were not locked properly. This is now fixed by ignoring `DELAYED` in this context. (Bug#1983)

- Replication: Sometimes the master gets a non-fatal error during the execution of a statement that does not immediately succeed. (For example, a write to a `MyISAM` table may first receive ``no space left on device,'' but later complete when disk space becomes available. See Section A.4.3, « Comment MySQL gère un disque plein ».) The bug was that the master forgot to reset the error code to 0 after success, so the error code got into its binary log, thus causing the slave to issue false alarms such as ``did not get the same error as on master.'' (Bug#2083)

- Removed a misleading ``check permissions on master.info'' from a replication error message, because the cause of the problem could be something other than permissions. (Bug#2121)

- Fixed a crash when the replication slave was unable to create the first relay log. (Bug#2145)

- Replication of `LOAD DATA INFILE` for an empty file from a 3.23 master to a 4.0 slave caused the slave to print an error. (Bug#2452)

- When automatically forcing `lower_case_table_names` to 1 if the file system was case insensitive, `mysqld` could crash. This bug existed only in MySQL 4.0.17. (Bug#2481)

- Restored ability to specify default values for `TIMESTAMP` columns that was erroneously disabled in previous release. (Bug#2539) Fixed `SHOW CREATE TABLE` to reflect these values. (Bug#1885) Note that because of the auto-update feature for the first `TIMESTAMP` column in a table, it makes no sense to specify a default value for the column. Any such default will be silently ignored (unless another `TIMESTAMP` column is added before this one). Also fixed the meaning of the `DEFAULT` keyword when it is used to specify the value to be inserted into a `TIMESTAMP` column other than the first. (Bug#2464)

- Fixed bug for out-of-range arguments on QNX platform that caused `UNIX_TIMESTAMP()` to produce incorrect results or that caused non-zero values to be inserted into `TIMESTAMP` columns. (Bug#2523) Also, current time zone now is taken into account when checking if datetime values satisfy both range boundaries for `TIMESTAMP` columns. The range allowed for a `TIMESTAMP` column is time zone-dependent and equivalent to a range of `1970-01-01 00:00:01` UTC to `2037-12-31 23:59:59` UTC.

- Multiple-table `DELETE` statements were never replicated by the slave if there were any `replicate-*-table` options. (Bug#2527)

- Changes to session counterparts of variables `query_prealloc_size`, `query_alloc_block_size`, `trans_prealloc_size`, `trans_alloc_block_size` now have an effect. (Bug#1948)

- Fixed bug in `ALTER TABLE RENAME`, when rename to the table with the same name in another database silently dropped destination table if it existed. (Bug#2628)

### C.3.9. Changements de la version 4.0.17 (14 décembre 2003)

Fonctionnalité ajoutée ou modifiée :

- `mysqldump` no longer dumps data for `MERGE` tables. (Bug#1846)

- `lower_case_table_names` is now forced to 1 if the database directory is located on a case-insensitive file system. (Bug#1812)

- Symlink creation is now disabled on systems where `realpath()` doesn't work. (Before one could use `CREATE TABLE .. DATA DIRECTORY=..` even if `HAVE_BROKEN_REALPATH` was defined. This is now disabled to avoid problems when running `ALTER TABLE`).

- Inserting a negative `AUTO_INCREMENT` value in a `MyISAM` table no longer updates the `AUTO_INCREMENT` counter to a big unsigned value. (Bug#1366)

- Added four new modes to `WEEK(..., mode)` function. See `WEEK(date: (mode)`). (Bug#1178)

- Allow `UNION DISTINCT` syntax.

- `mysql_server_init()` now returns 1 if it can't initialize the environment. (Previously `mysql_server_init()` called `exit(1)` if it could not create a key with `pthread_key_create()`. (Bug#2062)

- Allow spaces in Windows service names.

- Changed the default Windows service name for `mysqld` from `MySql` to MySQL. This should not affect usage, because service names are not case sensitive.

- When you install `mysqld` as a service on Windows systems, `mysqld` will read startup options in option files from the option group with the same name as the service name. (Except when the service name is MySQL).

Bogues corrigés :

- One can now configure MySQL as a Windows service as a normal user. (Bug#1802). Thanks to Richard Hansen for fixing this.

- Database names are now compared in lowercase in `ON` clauses when `lower_case_table_names` is set. (Bug#1736)

- `IGNORE ... LINES` option to `LOAD DATA INFILE` didn't work when used with fixed length rows. (Bug#1704)

- Fixed problem with `UNIX_TIMESTAMP()` for timestamps close to 0. (Bug#1998)

- Fixed problem with character values greater than 128 in the `QUOTE()` function. (Bug#1868)

- Fixed searching of `TEXT` with end space. (Bug#1651)

- Fixed caching bug in multiple-table updates where same table was used twice. (Bug#1711)

- Fixed directory permissions for the MySQL-server RPM documentation directory. (Bug#1672)

- Fixed server crash when updating an `ENUM` column that is set to the empty string (for example, with `REPLACE()`). (Bug#2023)

- `mysql` client program now correctly prints connection identifier returned by `mysql_thread_id()` as unsigned integer rather than as signed integer. (Bug#1951)

- `FOUND_ROWS()` could return incorrect number of rows after a query with an impossible `WHERE` condition. (Bug#1468)

- `SHOW DATABASES` no longer shows `.sym` files (on Windows) that do not point to a valid directory. (Bug#1385)

- Fixed a possible memory leak on Mac OS X when using the shared `libmysql.so` library. (from `pthread_key_create()`). (Bug#2061)

- Fixed bug in `UNION` statement with alias `*`. (Bug#1249)

- Fixed a bug in `DELETE ... ORDER BY ... LIMIT` where the rows where not deleted in the proper order. (Bug#1024, Bug#1697).

- Fixed serious problem with multi-threaded programs on Windows that used the embedded MySQL libraries. (Locks of tables were not handled correctly between different threads).

- Code cleanup: Fixed a few code defects (potential memory leaks, null pointer dereferences, uninitialized variables). Thanks to Reasoning Inc. for informing us about these findings.

- Fixed a buffer overflow error that occurred with prepended ‘`0`’ characters in some columns of type `DECIMAL`. (Bug#2128)

- Filesort was never shown in `EXPLAIN` if query contained an `ORDER BY NULL` clause. (Bug#1335)

- Fixed invalidation of whole query cache on `DROP DATABASE`. (Bug#1898)

- Fixed bug in range optimizer that caused wrong results for some unlikely `AND`/`OR` queries. (Bug#1828)

- Fixed a crash in `ORDER BY` when ordering by expression and identifier. (Bug#1945)

- Fixed a crash in an open `HANDLER` when an `ALTER TABLE` was executed in a different connection. (Bug#1826)

- Fixed a bug in `trunc*` operator of full-text search which sometimes caused MySQL not to find all matched rows.

- Fixed bug in prepending ‘`0`’ characters to `DECIMAL` column values.

- Fixed optimizer bug, introduced in 4.0.16, when `REF` access plan was preferred to more efficient `RANGE` on another column.

- Fixed problem when installing a MySQL server as a Windows service using a command of the form `mysqld --install mysql --defaults-file=path-to-file`. (Bug#1643)

- Fixed an incorrect result from a query that uses only `const` tables (such as one-row tables) and non-constant expression (such as `RAND()`). (Bug#1271)

- Fixed bug when the optimizer did not take `SQL_CALC_FOUND_ROWS` into account if `LIMIT` clause was present. (Bug#1274)

- `mysqlbinlog` now asks for a password at the console when the `-p` or `--password` option is used with no argument. This is consistent with the way that other clients such `mysqladmin` and `mysqldump` already behave. Note: A consequence of this change is that it is no longer possible to invoke `mysqlbinlog` as `mysqlbinlog -p pass_val` (with a space between the `-p` option and the following password value). (Bug#1595)

- Fixed bug accidentally introduced in 4.0.16 where the slave SQL thread deleted its replicated temporary tables when `STOP SLAVE` was issued.

- In a ``chain'' replication setup `A->B->C`, if 2 sessions on A updated temporary tables of the same name at the same time, the binary log of `B` became incorrect, resulting in `C` becoming confused. (Bug#1686)

- In a ``chain'' replication setup `A->B->C`, if `STOP SLAVE` was issued on `B` while it was replicating a temporary table from `A`, then when `START SLAVE` was issued on `B`, the binary log of `B` became incorrect, resulting in `C` becoming confused. (Bug#1240)

- When `MASTER_LOG_FILE` and `MASTER_LOG_POS` were not specified, `CHANGE MASTER` used the coordinates of the slave I/O thread to set up replication, which broke replication if the slave SQL thread lagged behind the slave I/O thread. This caused the slave SQL thread to lose some events. The new behavior is to use the coordinates of the slave SQL thread instead. See Section 13.6.2.1, « `CHANGE MASTER TO` ». (Bug#1870)

- Now if integer is stored or converted to `TIMESTAMP` or `DATETIME` value checks of year, month, day, hour, minute and second ranges are performed and numbers representing illegal timestamps are converted to 0 value. This behavior is consistent with manual and with behavior of string to `TIMESTAMP`/`DATETIME` conversion. (Bug#1448)

- Fixed bug when `BIT_AND()` and `BIT_OR()` group functions returned incorrect value if `SELECT` used a temporary table and no rows were found. (Bug#1790).

- `BIT_AND()` is now unsigned in all contexts. This means that it will now return 18446744073709551615 (= 0xffffffffffffffff) instead of -1 if there were no rows in the result.

- Fixed bug with `BIT_AND()` still returning signed value for an empty set in some cases. (Bug#1972)

- Fixed bug with `^` (XOR) and `>>` (bit shift) still returning signed value in some cases. (Bug#1993)

- Replication: a rare race condition in the slave SQL thread, which could lead to a wrong complain that the relay log is corrupted. (Bug#2011)

- Replication: if an administrative command on a table (`OPTIMIZE TABLE`, `REPAIR TABLE` etc) was run on the slave, this could sometimes stop the slave SQL thread (this did not led to any corruption; one just had to type `START SLAVE` to get replication going again). (Bug#1858)

- Replication: in the slave SQL thread, a multi-table `UPDATE` could produce a wrong complain that some record was not found in one table, if the `UPDATE` was preceded by a `INSERT ... SELECT`. (Bug#1701)

- Fixed deficiency in MySQL code which is responsible for scanning directories. This deficiency caused `SHOW TABLE STATUS` to be very slow for big number of tables in database even if single particular table were specified. (Bug#1952)

### C.3.10. Changements de la version 4.0.16 (17 octobre 2003)

Fonctionnalité ajoutée ou modifiée :

- Option values in option files now may be quoted. This is useful for values that contain whitespace or comment characters.

- Write memory allocation information to error log when doing `mysqladmin debug`. This works only on systems that support the `mallinfo()` call (like newer Linux systems).

- Added the following new server variables to allow more precise memory allocation: `range_alloc_block_size`, `query_alloc_block_size`, `query_prealloc_size`, `transaction_alloc_block_size`, and `transaction_prealloc_size`.

- `mysqlbinlog` now reads option files. To make this work, you must now specify `--read-from-remote-server` when reading binary logs from a MySQL server. (Note that using a remote server is deprecated and may disappear in future `mysqlbinlog` versions).

- Block `SIGPIPE` signals also for non-threaded programs. The blocking is moved from `mysql_init()` to `mysql_server_init()`, which is automatically called on the first call to `mysql_init()`.

- Added `--libs_r` and `--include` options to `mysql_config`.

- New ``>` prompt for `mysql`. This prompt is similar to the `'>` and `">` prompts, but indicates that an identifier quoted with backticks was begun on an earlier line and the closing backtick has not yet been seen.

- Updated `mysql_install_db` to be able to use the local machine's IP address instead of the hostname when building the initial grant tables if `skip-name-resolve` has been specified. This option can be helpful on FreeBSD to avoid thread-safety problems with the FreeBSD resolver libraries. (Thanks to Jeremy Zawodny for the patch.)

- A documentation change: Added a note that when backing up a slave, it is necessary also to back up the `master.info` and `relay-log.info` files, as well as any `SQL_LOAD-*` files located in the directory specified by the `--slave-load-tmpdir` option. All these files are needed when the slave resumes replication after you restore the slave's data.

Bogues corrigés :

- Fixed a spurious error `ERROR 14: Can't change size of file (Errcode: 2)` on Windows in `DELETE FROM tbl_name` without a `WHERE` clause or `TRUNCATE TABLE tbl_name`, when `tbl_name` is a `MyISAM` table. (Bug#1397)

- Fixed a bug that resulted in `thr_alarm queue is full` warnings after increasing the `max_connections` variable with `SET GLOBAL`. (Bug#1435)

- Made `LOCK TABLES` to work when `Lock_tables_priv` is granted on the database level and `Select_priv` is granted on the table level.

- Fixed crash of `FLUSH QUERY CACHE` on queries that use same table several times (Bug#988).

- Fixed core dump bug when setting an enum system variable (such as `SQL_WARNINGS`) to `NULL`.

- Extended the default timeout value for Windows clients from 30 seconds to 1 year. (The timeout that was added in MySQL 4.0.15 was way too short). This fixes a bug that caused `ERROR 2013: Lost connection to MySQL server during query` for queries that lasted longer than 30 seconds, if the client didn't specify a limit with `mysql_options()`. Users of 4.0.15 on Windows should upgrade to avoid this problem.

- More ``out of memory'' checking in range optimizer.

- Fixed and documented a problem when setting and using a user variable within the same `SELECT` statement. (Bug#1194).

- Fixed bug in overrun check for `BLOB` values with compressed tables. This was a bug introduced in 4.0.14. It caused MySQL to regard some correct tables containing `BLOB` values as corrupted. (Bug#770, Bug#1304, and maybe Bug#1295)

- `SHOW GRANTS` showed `USAGE` instead of the real column-level privileges when no table-level privileges were given.

- When copying a database from the master, `LOAD DATA FROM MASTER` dropped the corresponding database on the slave, thus erroneously dropping tables that had no counterpart on the master and tables that may have been excluded from replication using `replicate-*-table` rules. Now `LOAD DATA FROM MASTER` no longer drops the database. Instead, it drops only the tables that have a counterpart on the master and that match the `replicate-*-table` rules. `replicate-*-db` rules can still be used to include or exclude a database as a whole from `LOAD DATA FROM MASTER`. A database will also be included or excluded as a whole if there are some rules like `replicate-wild-do-table=db1.%` or `replicate-wild-ignore-table=db1.%`, as is already the case for `CREATE DATABASE` and `DROP DATABASE` in replication. (Bug#1248)

- Fixed a bug where `mysqlbinlog` crashed with a segmentation fault when used with the `-h` or `--host` option. (Bug#1258)

- Fixed a bug where `mysqlbinlog` crashed with a segmentation fault when used on a binary log containing only final events for `LOAD DATA`. (Bug#1340)

- `mysqlbinlog` will not reuse temporary file names from previous runs. Previously `mysqlbinlog` failed if was used several times on the same binary log file that contained a `LOAD DATA` command.

- Fixed compilation problem when compiling with OpenSSL 0.9.7 with disabled old DES support (If `OPENSSL_DISABLE_OLD_DES_SUPPORT` option was enabled).

- Fixed a bug when two (or more) MySQL servers were running on the same machine, and they were both slaves, and at least one of them was replicating some `LOAD DATA INFILE` command from its master. The bug was that one slave MySQL server sometimes deleted the `SQL_LOAD-*` files (used for replication of `LOAD DATA INFILE` and located in the `slave-load-tmpdir` directory, which defaults to `tmpdir`) belonging to the other slave MySQL server of this machine, if these slaves had the same `slave-load-tmpdir` directory. When that happened, the other slave could not replicate `LOAD DATA INFILE` and complained about not being able to open some `SQL_LOAD-*` file. (Bug#1357)

- If `LOAD DATA INFILE` failed for a small file, the master forgot to write a marker (a `Delete_file` event) in its binary log, so the slave could not delete 2 files (`SQL_LOAD-*.info` and `SQL_LOAD-*.data` from its `tmpdir`. (Bug#1391)

- On Windows, the slave forgot to delete a `SQL_LOAD-*.info` file from `tmpdir` after successfully replicating a `LOAD DATA INFILE` command. (Bug#1392)

- When a connection terminates, MySQL writes `DROP TEMPORARY TABLE` statements to the binary log for all temporary tables which the connection had not explicitly dropped. MySQL forgot to use backticks to quote the database and table names in the statement. (Bug#1345)

- On some 64-bit machines (some HP-UX and Solaris machines), a slave installed with the 64-bit MySQL binary could not connect to its master (it connected to itself instead). (Bug#1256, Bug#1381)

- Code was introduced in MySQL 4.0.15 for the slave to detect that the master had died while writing a transaction to its binary log. This code reported an error in a legal situation: When the slave I/O thread was stopped while copying a transaction to the relay log, the slave SQL thread would later pretend that it found an unfinished transaction. (Bug#1475)

### C.3.11. Changements de la version 4.0.15 (03 septembre 2003)

IMPORTANT:

If you are using this release on Windows, you should upgrade at least your clients (any program that uses `libmysql.lib`) to 4.0.16 or above. This is because the 4.0.15 release had a bug in the Windows client library that causes Windows clients using the library to die with a `Lost connection to MySQL server during query` error for queries that take more than 30 seconds. This problem is specific to Windows; clients on other platforms are unaffected.

Fonctionnalité ajoutée ou modifiée :

- `mysqldump` now correctly quotes all identifiers when communicating with the server. This assures that during the dump process, `mysqldump` will never send queries to the server that result in a syntax error. This problem is not related to the `mysqldump` program's output, which was not changed. (Bug#1148)

- Change result set metadata information so that `MIN()` and `MAX()` report that they can return `NULL` (this is true because an empty set will return `NULL`). (Bug#324)

- Produce an error message on Windows if a second `mysqld` server is started on the same TCP/IP port as an already running `mysqld` server.

- The `mysqld` server variables `wait_timeout`, `net_read_timeout`, and `net_write_timeout` now work on Windows. One can now also set timeouts for read and writes in Windows clients with `mysql_options()`.

- Added option `--sql-mode=NO_DIR_IN_CREATE` to make it possible for slaves to ignore `INDEX DIRECTORY` and `DATA DIRECTORY` options given to `CREATE TABLE`. When this is mode is on, `SHOW CREATE TABLE` will not show the given directories.

- `SHOW CREATE TABLE` now shows the `INDEX DIRECTORY` and `DATA DIRECTORY` options, if they were specified when the table was created.

- The `open_files_limit` server variable now shows the real open files limit.

- `MATCH ... AGAINST()` in natural language mode now treats words that are present in more than 2,000,000 rows as stopwords.

- The Mac OS X installation disk images now include an additional `MySQLStartupItem.pkg` package that enables the automatic startup of MySQL on system bootup. See Section 2.2.13, « Installer MySQL sur Mac OS X ».

- Most of the documentation included in the binary tarball distributions (`.tar.gz`) has been moved into a subdirectory `docs`. See Section 2.1.5, « Dispositions d'installation ».

- The manual is now included as an additional `info` file in the binary distributions. (Bug#1019)

- The binary distributions now include the embedded server library (`libmysqld.a`) by default. Due to a linking problem with non-gcc compilers, it was not included in all packages of the initial 4.0.15 release. The affected packages were rebuilt and released as 4.0.15a. See Section 1.3.1.2, « MySQL Server intégré (embedded) ».

- MySQL can now use range optimization for `BETWEEN` with non-constant limits. (Bug#991)

- Replication error messages now include the default database, so that users can check which database the failing query was run for.

- A documentation change: Added a paragraph about how the `binlog-do-db` and `binlog-ignore-db` options are tested against the database on the master (see Section 5.9.4, « Le log binaire »), and a paragraph about how `replicate-do-db`, `replicate-do-table` and analogous options are tested against the database and tables on the slave (see Section 6.8, « Options de démarrage de la réplication »).

- Now the slave does not replicate `SET PASSWORD` if it is configured to exclude the `mysql` database from replication (using for example `replicate-wild-ignore-table=mysql.%`). This was already the case for `GRANT` and `REVOKE` since version 4.0.13 (though there was Bug#980 in 4.0.13 & 4.0.14, which has been fixed in 4.0.15).

- Rewrote the information shown in the `State` column of `SHOW PROCESSLIST` for replication threads and for `MASTER_POS_WAIT()` and added the most common states for these threads to the documentation, see Section 6.3, « Détails d'implémentation de la réplication ».

- Added a test in replication to detect the case where the master died in the middle of writing a transaction to the binlog; such unfinished transactions now trigger an error message on the slave.

- A `GRANT` command that creates an anonymous user (that is, an account with an empty username) no longer requires `FLUSH PRIVILEGES` for the account to be recognized by the server. (Bug#473)

- `CHANGE MASTER` now flushes `relay-log.info`. Previously this was deferred to the next run of `START SLAVE`, so if `mysqld` was shutdown on the slave after `CHANGE MASTER` without having run `START SLAVE`, the relay log's name and position were lost. At restart they were reloaded from `relay-log.info`, thus reverting to their old (incorrect) values from before `CHANGE MASTER` and leading to error messages (as the old relay log did not exist any more) and the slave threads refusing to start. (Bug#858)

Bogues corrigés :

- Fixed buffer overflow in password handling which could potentially be exploited by MySQL users with `ALTER` privilege on the `mysql.user` table to execute random code or to gain shell access with the UID of the mysqld process (thanks to Jedi/Sector One for spotting and reporting this bug).

- Fixed server crash on `FORCE INDEX` in a query that contained "Range checked for each record" in the `EXPLAIN` output. (Bug#1172)

- Fixed table/column grant handling - proper sort order (from most specific to less specific, see Section 5.5.6, « Contrôle d'accès, étape 2 : Vérification de la requête ») was not honored. (Bug#928)

- Fixed rare bug in MYISAM introduced in 4.0.3 where the index file header was not updated directly after an `UPDATE` of split dynamic rows. The symptom was that the table had a corrupted delete-link if mysqld was shut down or the table was checked directly after the update.

- Fixed `Can't unlock file` error when running `myisamchk --sort-index` on Windows. (Bug#1119)

- Fixed possible deadlock when changing `key_buffer_size` while the key cache was actively used. (Bug#1088)

- Fixed overflow bug in `MyISAM` and `ISAM` when a row is updated in a table with a large number of columns and at least one `BLOB/TEXT` column.

- Fixed incorrect result when doing `UNION` and `LIMIT #,#` when one didn't use braces around the `SELECT` parts.

- Fixed incorrect result when doing `UNION` and `ORDER BY .. LIMIT #` when one didn't use braces around the `SELECT` parts.

- Fixed problem with `SELECT SQL_CALC_FOUND_ROWS ... UNION ALL ... LIMIT #` where `FOUND_ROWS()` returned incorrect number of rows.

- Fixed unlikely stack bug when having a BIG expression of type `1+1-1+1-1...` in certain combinations. (Bug#871)

- Fixed the bug that sometimes prevented a table with a `FULLTEXT` index from being marked as "analyzed".

- Fixed MySQL so that the column length (in C API) for the second column in `SHOW CREATE TABLE` is always larger than the data length. The only known application that was affected by the old behavior was Borland dbExpress, which truncated the output from the command. (Bug#1064)

- Fixed crash in comparisons of strings using the `tis620` character set. (Bug#1116)

- Fixed `ISAM` bug in `MAX()` optimization.

- `myisamchk --sort-records=N` no longer marks table as crashed if sorting failed because of an inappropriate key. (Bug#892)

- Fixed a minor bug in `MyISAM` compressed table handling that sometimes made it impossible to repair compressed table in "Repair by sort" mode. "Repair with keycache" (`myisamchk --safe-recover`) worked, though. (Bug#1015)

- Fixed bug in propagating the version number to the manual included in the distribution files. (Bug#1020)

- Fixed key sorting problem (a `PRIMARY` key declared for a column that is not explicitly marked `NOT NULL` was sorted after a `UNIQUE` key for a `NOT NULL` column).

- Fixed the result of `INTERVAL` when applied to a `DATE` value. (Bug#792)

- Fixed compiling of the embedded server library in the RPM spec file. (Bug#959)

- Added some missing files to the RPM spec file and fixed some RPM building errors that occurred on Red Hat Linux 9. (Bug#998)

- Fixed incorrect `XOR` evaluation in `WHERE` clause. (Bug#992)

- Fixed bug with processing in query cache merged tables constructed from more then 255 tables. (Bug#930)

- Fixed incorrect results from outer join query (e.g. `LEFT JOIN`) when `ON` condition is always false, and range search in used. (Bug#926)

- Fixed a bug causing incorrect results from `MATCH ... AGAINST()` in some joins. (Bug#942)

- `MERGE` tables do not ignore "Using index" (from `EXPLAIN` output) anymore.

- Fixed a bug that prevented an empty table from being marked as "analyzed". (Bug#937)

- Fixed `myisamchk --sort-records` crash when used on compressed table.

- Fixed slow (as compared to 3.23) `ALTER TABLE` and related commands such as `CREATE INDEX`. (Bug#712)

- Fixed segmentation fault resulting from `LOAD DATA FROM MASTER` when the master was running without the `--log-bin` option. (Bug#934)

- Fixed a security bug: A server compiled without SSL support still allowed connections by users that had the `REQUIRE SSL` option specified for their accounts.

- Fixed a random bug: Sometimes the slave would replicate `GRANT` or `REVOKE` queries even if it was configured to exclude the `mysql` database from replication (for example, using `replicate-wild-ignore-table=mysql.%`). (Bug#980)

- The `Last_Errno` and `Last_Error` fields in the output of `SHOW SLAVE STATUS` are now cleared by `CHANGE MASTER` and when the slave SQL thread starts. (Bug#986)

- A documentation mistake: It said that `RESET SLAVE` does not change connection information (master host, port, user, and password), whereas it does. The statement resets these to the startup options (`master-host` etc) if there were some. (Bug#985)

- `SHOW SLAVE STATUS` now shows correct information (master host, port, user, and password) after `RESET SLAVE` (that is, it shows the new values, which are copied from the startup options if there were some). (Bug#985)

- Disabled propagation of the original master's log position for events because this caused unexpected values for `Exec_Master_Log_Pos` and problems with `MASTER_POS_WAIT()` in A->B->C replication setup. (Bug#1086)

- Fixed a segfault in `mysqlbinlog` when `--position=x` was used with `x` being between a `Create_file` event and its fellow `Append_block`, `Exec_load` or `Delete_file` events. (Bug#1091)

- `mysqlbinlog` printed superfluous warnings when using `--database`, which caused syntax errors when piped to `mysql`. (Bug#1092)

- Made `mysqlbinlog --database` filter `LOAD DATA INFILE` too (previously, it filtered all queries except `LOAD DATA INFILE`). (Bug#1093)

- `mysqlbinlog` in some cases forgot to put a leading `'#'` in front of the original `LOAD DATA INFILE` (this command is displayed only for information, not to be run; it is later reworked to `LOAD DATA LOCAL` with a different filename, for execution by `mysql`). (Bug#1096)

- `binlog-do-db` and `binlog-ignore-db` incorrectly filtered `LOAD DATA INFILE` (it was half-written to the binary log). This resulted in a corrupted binary log, which could cause the slave to stop with an error. (Bug#1100)

- When, in a transaction, a transactional table (such as an `InnoDB` table) was updated, and later in the same transaction a non-transactional table (such as a `MyISAM` table) was updated using the updated content of the transactional table (with `INSERT ... SELECT` for example), the queries were written to the binary log in an incorrect order. (Bug#873)

- When, in a transaction, `INSERT ... SELECT` updated a non-transactional table, and `ROLLBACK` was issued, no error was returned to the client. Now the client is warned that some changes could not be rolled back, as this was already the case for normal `INSERT`. (Bug#1113)

- Fixed a potential bug: When `STOP SLAVE` was run while the slave SQL thread was in the middle of a transaction, and then `CHANGE MASTER` was used to point the slave to some non-transactional statement, the slave SQL thread could get confused (because it would still think, from the past, that it was in a transaction).

### C.3.12. Changements de la version 4.0.14 (18 juillet 2003)

Fonctionnalité ajoutée ou modifiée :

- Added `default_week_format` system variable. The value is used as the default mode for the `WEEK()` function.

- `mysqld` now reads an additional option file group having a name corresponding to the server's release series: `[mysqld-4.0]` for 4.0.x servers, `[mysqld-4.1]` for 4.1.x servers, and so forth. This allows options to be specified on a series-specific basis.

- The `CONCAT_WS()` function no longer skips empty strings. (Bug#586).

- `InnoDB` now supports indexing a prefix of a column. This means, in particular, that `BLOB` and `TEXT` columns can be indexed in `InnoDB` tables, which was not possible before.

- A documentation change: Function `INTERVAL(NULL, ...)` returns `-1`.

- Enabled `INSERT` from `SELECT` when the table into which the records are inserted is also a table listed in the `SELECT`.

- Allow `CREATE TABLE` and `INSERT` from any `UNION`.

- The `SQL_CALC_FOUND_ROWS` option now always returns the total number of rows for any `UNION`.

- Removed `--table` option from `mysqlbinlog` to avoid repeating `mysqldump` functionality.

- Comment lines in option files can now start from the middle of a line, too (like `basedir=c:\mysql # installation directory`).

- Changed optimizer slightly to prefer index lookups over full table scans in some boundary cases.

- Added thread-specific `max_seeks_for_key` variable that can be used to force the optimizer to use keys instead of table scans even if the cardinality of the index is low.

- Added optimization that converts `LEFT JOIN` to normal join in some cases.

- A documentation change: added a paragraph about failover in replication (how to use a surviving slave as the new master, how to resume to the original setup). See Section 6.9, « FAQ de la réplication ».

- A documentation change: added warning notes about safe use of the `CHANGE MASTER` command. See Section 13.6.2.1, « `CHANGE MASTER TO` ».

- MySQL now issues a warning (not an error, as in 4.0.13) when it opens a table that was created with MySQL 4.1.

- Added `--nice` option to `mysqld_safe` to allow setting the niceness of the `mysqld` process. (Thanks to Christian Hammers for providing the initial patch.) (Bug#627)

- Added `--read-only` option to cause `mysqld` to allow no updates except from slave threads or from users with the `SUPER` privilege. (Original patch from Markus Benning).

- `SHOW BINLOG EVENTS FROM x` where `x` is less than 4 now silently converts `x` to 4 instead of printing an error. The same change was done for `CHANGE MASTER TO MASTER_LOG_POS=x` and `CHANGE MASTER TO RELAY_LOG_POS=x`.

- `mysqld` now only adds an interrupt handler for the `SIGINT` signal if you start it with the new `--gdb` option. This is because some MySQL users encountered strange problems when they accidentally sent `SIGINT` to `mysqld` threads.

- `RESET SLAVE` now clears the `Last_Errno` and `Last_Error` fields in the output of `SHOW SLAVE STATUS`.

- Added `max_relay_log_size` variable; the relay log will be rotated automatically when its size exceeds `max_relay_log_size`. But if `max_relay_log_size` is 0 (the default), `max_binlog_size` will be used (as in older versions). `max_binlog_size` still applies to binary logs in any case.

- `FLUSH LOGS` now rotates relay logs in addition to the other types of logs it already rotated.

Bogues corrigés :

- Comparison/sorting for `latin1_de` character set was rewritten. The old algorithm could not handle cases like `"sä" > "ßa"`. See Section 5.8.1.1, « Jeu de caractères allemand ». In rare cases it resulted in table corruption.

- Fixed a problem with the password prompt on Windows. (Bug#683)

- `ALTER TABLE ... UNION=(...)` for `MERGE` table is now allowed even if some underlying `MyISAM` tables are read-only. (Bug#702)

- Fixed a problem with `CREATE TABLE t1 SELECT x'41'`. (Bug#801)

- Removed some incorrect lock warnings from the error log.

- Fixed memory overrun when doing `REPAIR TABLE` on a table with a multiple-part auto_increment key where one part was a packed `CHAR`.

- Fixed a probable race condition in the replication code that could potentially lead to `INSERT` statements not being replicated in the event of a `FLUSH LOGS` command or when the binary log exceeds `max_binlog_size`. (Bug#791)

- Fixed a crashing bug in `INTERVAL` and `GROUP BY` or `DISTINCT`. (Bug#807)

- Fixed bug in `mysqlhotcopy` so it actually aborts for unsuccessful table copying operations. Fixed another bug so that it succeeds when there are thousands of tables to copy. (Bug#812)

- Fixed problem with `mysqlhotcopy` failing to read options from option files. (Bug#808)

- Fixed bugs in optimizer that sometimes prevented MySQL from using `FULLTEXT` indexes even though it was possible (for example, in `SELECT * FROM t1 WHERE MATCH a,b AGAINST("index") > 0`).

- Fixed a bug with ``table is full'' in `UNION` operations.

- Fixed a security problem that enabled users with no privileges to obtain information on the list of existing databases by using `SHOW TABLES` and similar commands.

- Fixed a stack problem on UnixWare/OpenUnix.

- Fixed a configuration problem on UnixWare/OpenUNIX and OpenServer.

- Fixed a stack overflow problem in password verification.

- Fixed a problem with `max_user_connections`.

- `HANDLER` without an index now works properly when a table has deleted rows. (Bug#787)

- Fixed a bug with `LOAD DATA` in `mysqlbinlog`. (Bug#670)

- Fixed that `SET CHARACTER SET DEFAULT` works. (Bug#462)

- Fixed `MERGE` table behavior in `ORDER BY ... DESC` queries. (Bug#515)

- Fixed server crash on `PURGE MASTER LOGS` or `SHOW MASTER LOGS` when the binary log is off. (Bug#733)

- Fixed password-checking problem on Windows. (Bug#464)

- Fixed the bug in comparison of a `DATETIME` column and an integer constant. (Bug#504)

- Fixed remote mode of `mysqlbinlog`. (Bug#672)

- Fixed `ERROR 1105: Unknown error` that occurred for some `SELECT` queries, where a column that was declared as `NOT NULL` was compared with an expression that took `NULL` value.

- Changed timeout in `mysql_real_connect()` to use `poll()` instead of `select()` to work around problem with many open files in the client.

- Fixed incorrect results from `MATCH ... AGAINST` used with a `LEFT JOIN` query.

- Fixed a bug that limited the maximum value for `mysqld` variables to 4294967295 when they are specified on the command line.

- Fixed a bug that sometimes caused spurious ``Access denied'' errors in `HANDLER ... READ` statements, when a table is referenced via an alias.

- Fixed portability problem with `safe_malloc`, which caused MySQL to give "Freeing wrong aligned pointer" errors on SCO 3.2.

- `ALTER TABLE ... ENABLE/DISABLE KEYS` could cause a core dump when done after an `INSERT DELAYED` statement on the same table.

- Fixed problem with conversion of localtime to GMT where some times resulted in different (but correct) timestamps. Now MySQL should use the smallest possible timestamp value in this case. (Bug#316)

- Very small query cache sizes could crash `mysqld`. (Bug#549)

- Fixed a bug (accidentally introduced by us but present only in version 4.0.13) that made `INSERT ... SELECT` into an `AUTO_INCREMENT` column not replicate well. This bug is in the master, not in the slave. (Bug#490)

- Fixed a bug : When an `INSERT ... SELECT` statement inserted rows into a non-transactional table, but failed at some point (for example, due to a ``Duplicate key'' error), the query was not written to the binary log. Now it is written to the binary log, with its error code, as all other queries are. About the `slave-skip-errors` option for how to handle partially completed queries in the slave, see Section 6.8, « Options de démarrage de la réplication ». (Bug#491)

- `SET FOREIGN_KEY_CHECKS=0` was not replicated properly. The fix probably will not be backported to 3.23.

- On a slave, `LOAD DATA INFILE` which had no `IGNORE` or `REPLACE` clause on the master, was replicated with `IGNORE`. While this is not a problem if the master and slave data are identical (a `LOAD` that produces no duplicate conflicts on the master will produce none on the slave anyway), which is true in normal operation, it is better for debugging not to silently add the `IGNORE`. That way, you can get an error message on the slave and discover that for some reason, the data on master and slave are different and investigate why. (Bug#571)

- On a slave, `LOAD DATA INFILE` printed an incomplete ``Duplicate entry '%-.64s' for key %d''' message (the key name and value were not mentioned) in case of duplicate conflict (which does not happen in normal operation). (Bug#573)

- When using a slave compiled with `--debug`, `CHANGE MASTER TO RELAY_LOG_POS` could cause a debug assertion failure. (Bug#576)

- When doing a `LOCK TABLES WRITE` on an `InnoDB` table, commit could not happen, if the query was not written to the binary log (for example, if `--log-bin` was not used, or `binlog-ignore-db` was used). (Bug#578)

- If a 3.23 master had open temporary tables that had been replicated to a 4.0 slave, and the binary log got rotated, these temporary tables were immediately dropped by the slave (which caused problems if the master used them subsequently). This bug had been fixed in 4.0.13, but in a manner which caused an unlikely inconvenience: If the 3.23 master died brutally (power failure), without having enough time to automatically write `DROP TABLE` statements to its binary log, then the 4.0.13 slave would not notice the temporary tables have to be dropped, until the slave `mysqld` server is restarted. This minor inconvenience is fixed in 3.23.57 and 4.0.14 (meaning the master must be upgraded to 3.23.57 and the slave to 4.0.14 to remove the inconvenience). (Bug#254)

- If `MASTER_POS_WAIT()` was waiting, and the slave was idle, and the slave SQL thread terminated, `MASTER_POS_WAIT()` would wait forever. Now when the slave SQL thread terminates, `MASTER_POS_WAIT()` immediately returns `NULL` (``slave stopped''). (Bug#651)

- After `RESET SLAVE; START SLAVE;`, the `Relay_Log_Space` value displayed by `SHOW SLAVE STATUS` was too big by four bytes. (Bug#763)

- If a query was ignored on the slave (because of `replicate-ignore-table` and other similar rules), the slave still checked if the query got the same error code (0, no error) as on the master. So if the master had an error on the query (for example, ``Duplicate entry'' in a multiple-row insert), then the slave stopped and warned that the error codes didn't match. (Bug#797)

### C.3.13. Changements de la version 4.0.13 (16 Mai 2003)

Fonctionnalité ajoutée ou modifiée :

- `PRIMARY KEY` now implies `NOT NULL`. (Bug#390)

- The Windows binary packages are now compiled with `--enable-local-infile` to match the Unix build configuration.

- Removed timing of tests from `mysql-test-run`. `time` does not accept all required parameters on many platforms (for example, QNX) and timing the tests is not really required (it's not a benchmark anyway).

- `SHOW MASTER STATUS` and `SHOW SLAVE STATUS` required the `SUPER` privilege; now they accept `REPLICATION CLIENT` as well. (Bug#343)

- Added multi-threaded `MyISAM` repair optimization and `myisam_repair_threads` variable to enable it. See Section 5.2.3, « Variables serveur système ».

- Added `innodb_max_dirty_pages_pct` variable which controls amount of dirty pages allowed in `InnoDB` buffer pool.

- `CURRENT_USER()` and `Access denied` error messages now report the hostname exactly as it was specified in the `GRANT` command.

- Removed benchmark results from the source and binary distributions. They are still available in the BK source tree, though.

- `InnoDB` tables now support `ANALYZE TABLE`.

- MySQL now issues an error when it opens a table that was created with MySQL 4.1.

- Option `--new` now changes binary items (`0xFFDF`) to be treated as binary strings instead of numbers by default. This fixes some problems with character sets where it's convenient to input the string as a binary item. After this change you have to convert the binary string to `INTEGER` with a `CAST` if you want to compare two binary items with each other and know which one is bigger than the other. `SELECT CAST(0xfeff AS UNSIGNED) < CAST(0xff AS UNSIGNED)`. This will be the default behavior in MySQL 4.1. (Bug#152)

- Enabled `delayed_insert_timeout` on Linux (most modern `glibc` libraries have a fixed `pthread_cond_timedwait()`). (Bug#211)

- Don't create more insert delayed threads than given by `max_delayed_threads`. (Bug#211)

- Changed `UPDATE ... LIMIT` to apply the limit to rows that were matched, whether or not they actually were changed. Previously the limit was applied as a restriction on the number of rows changed.

- Tuned optimizer to favor clustered index over table scan.

- `BIT_AND()` and `BIT_OR()` now return an unsigned 64-bit value.

- Added warnings to error log of why a secure connection failed (when running with `--log-warnings`).

- Deprecated options `--skip-symlink` and `--use-symbolic-links` and replaced these with `--symbolic-links`.

- The default option for `innodb_flush_log_at_trx_commit` was changed from 0 to 1 to make `InnoDB` tables ACID by default. See Section 15.5, « Options de démarrage `InnoDB` ».

- Added a feature to `SHOW KEYS` to display keys that are disabled by `ALTER TABLE DISABLE KEYS` command.

- When using a non-existing table type with `CREATE TABLE`, first try if the default table type exists before falling back to `MyISAM`.

- Added `MEMORY` as an alias for `HEAP`.

- Renamed function `rnd` to `my_rnd` as the name was too generic and is an exported symbol in `libmysqlclient` (thanks to Dennis Haney for the initial patch).

- Portability fix: renamed `include/dbug.h` to `include/my_dbug.h`.

- `mysqldump` no longer silently deletes the binary logs when invoked with the `--master-data` or `--first-slave` option; while this behavior was convenient for some users, others may suffer from it. Now you must explicitly ask for binary logs to be deleted by using the new `--delete-master-logs` option.

- If the slave is configured (using for example `replicate-wild-ignore-table=mysql.%`) to exclude `mysql.user`, `mysql.host`, `mysql.db`, `mysql.tables_priv` and `mysql.columns_priv` from replication, then `GRANT` and `REVOKE` will not be replicated.

Bogues corrigés :

- Logged `Access denied` error message had incorrect `Using password` value. (Bug#398)

- Fixed bug with `NATURAL LEFT JOIN`, `NATURAL RIGHT JOIN` and `RIGHT JOIN` when using many joined tables. The problem was that the `JOIN` method was not always associated with the tables surrounding the `JOIN` method. If you have a query that uses many `RIGHT JOIN` or `NATURAL ... JOINS` you should verify that they work as you expected after upgrading MySQL to this version. (Bug#291)

- Fixed `mysql` parser not to erroneously interpret ‘`'`’ or ‘`"`’ characters within `/* ... */` comment as beginning a quoted string.

- `mysql` command line client no longer looks for `\*` commands inside backtick-quoted strings.

- Fixed `Unknown error` when using `UPDATE ... LIMIT`. (Bug#373)

- Fixed problem with ANSI mode and `GROUP BY` with constants. (Bug#387)

- Fixed bug with `UNION` and `OUTER JOIN`. (Bug#386)

- Fixed bug if one used a multiple-table `UPDATE` and the query required a temporary table bigger than `tmp_table_size`. (Bug#286)

- Run `mysql_install_db` with the `-IN-RPM` option for the Mac OS X installation to not fail on systems with improperly configured hostname configurations.

- `LOAD DATA INFILE` will now read `000000` as a zero date instead as `"2000-00-00"`.

- Fixed bug that caused `DELETE FROM table WHERE const_expression` always to delete the whole table (even if expression result was false). (Bug#355)

- Fixed core dump bug when using `FORMAT('nan',#)`. (Bug#284)

- Fixed name resolution bug with `HAVING ... COUNT(DISTINCT ...)`.

- Fixed incorrect result from truncation operator (`*`) in `MATCH ... AGAINST()` in some complex joins.

- Fixed a crash in `REPAIR ... USE_FRM` command, when used on read-only, nonexisting table or a table with a crashed index file.

- Fixed a crashing bug in `mysql` monitor program. It occurred if program was started with `--no-defaults`, with a prompt that contained the hostname and a connection to a non-existent database was requested.

- Fixed problem when comparing a key for a multi-byte character set. (Bug#152)

- Fixed bug in `LEFT`, `RIGHT` and `MID` when used with multi-byte character sets and some `GROUP BY` queries. (Bug#314)

- Fix problem with `ORDER BY` being discarded for some `DISTINCT` queries. (Bug#275)

- Fixed that `SET SQL_BIG_SELECTS=1` works as documented (This corrects a new bug introduced in 4.0)

- Fixed some serious bugs in `UPDATE ... ORDER BY`. (Bug#241)

- Fixed unlikely problem in optimizing `WHERE` clause with constant expression like in `WHERE 1 AND (a=1 AND b=1)`.

- Fixed that `SET SQL_BIG_SELECTS=1` works again.

- Introduced proper backtick quoting for db.table in `SHOW GRANTS`.

- `FULLTEXT` index stopped working after `ALTER TABLE` that converts `TEXT` column to `CHAR`. (Bug#283)

- Fixed a security problem with `SELECT` and wildcarded select list, when user only had partial column `SELECT` privileges on the table.

- Mark a `MyISAM` table as "analyzed" only when all the keys are indeed analyzed.

- Only ignore world-writable `my.cnf` files that are regular files (and not, for example, named pipes or character devices).

- Fixed few smaller issues with `SET PASSWORD`.

- Fixed error message which contained deprecated text.

- Fixed a bug with two `NATURAL JOIN`s in the query.

- `SUM()` didn't return `NULL` when there was no rows in result or when all values was `NULL`.

- On Unix symbolic links handling was not enabled by default and there was no way to turn this on.

- Added missing dashes to parameter `--open-files-limit` in `mysqld_safe`. (Bug#264)

- Fixed incorrect hostname for TCP/IP connections displayed in `SHOW PROCESSLIST`.

- Fixed a bug with `NAN` in `FORMAT(...)` function ...

- Fixed a bug with improperly cached database privileges.

- Fixed a bug in `ALTER TABLE ENABLE / DISABLE KEYS` which failed to force a refresh of table data in the cache.

- Fixed bugs in replication of `LOAD DATA INFILE` for custom parameters (`ENCLOSED`, `TERMINATED` and so on) and temporary tables. (Bug#183, Bug#222)

- Fixed a replication bug when the master is 3.23 and the slave 4.0: the slave lost the replicated temporary tables if `FLUSH LOGS` was issued on the master. (Bug#254)

- Fixed a bug when doing `LOAD DATA INFILE IGNORE`: When reading the binary log, `mysqlbinlog` and the replication code read `REPLACE` instead of `IGNORE`. This could make the slave's table become different from the master's table. (Bug#218)

- Fixed a deadlock when `relay_log_space_limit` was set to a too small value. (Bug#79)

- Fixed a bug in HAVING clause when an alias is used from the select list.

- Fixed overflow bug in `MyISAM` when a row is inserted into a table with a large number of columns and at least one `BLOB/TEXT` column. Bug was caused by incorrect calculation of the needed buffer to pack data.

- Fixed a bug when `SELECT` @nonexistent_variable caused the error in client - server protocol due to net_printf() being sent to the client twice.

- Fixed a bug in setting `SQL_BIG_SELECTS` option.

- Fixed a bug in `SHOW PROCESSLIST` which only displayed a localhost in the `"Host"` column. This was caused by a glitch that used only current thread information instead of information from the linked list of threads.

- Removed unnecessary Mac OS X helper files from server RPM. (Bug#144)

- Allow optimization of multiple-table update for `InnoDB` tables as well.

- Fixed a bug in multiple-table updates that caused some rows to be updated several times.

- Fixed a bug in `mysqldump` when it was called with `--master-data`: the `CHANGE MASTER TO` commands appended to the SQL dump had incorrect coordinates. (Bug#159)

- Fixed a bug when an updating query using `USER()` was replicated on the slave; this caused segfault on the slave. (Bug#178). `USER()` is still badly replicated on the slave (it is replicated to `""`).

### C.3.14. Changements de la version 4.0.12 (15 Mars 2003 : Production)

Fonctionnalité ajoutée ou modifiée :

- `mysqld` no longer reads options from world-writeable config files.

- Integer values between 9223372036854775807 and 9999999999999999999 are now regarded as unsigned longlongs, not as floats. This makes these values work similar to values between 10000000000000000000 and 18446744073709551615.

- `SHOW PROCESSLIST` will now include the client TCP port after the hostname to make it easier to know from which client the request originated.

Bogues corrigés :

- Fixed `mysqld` crash on extremely small values of `sort_buffer` variable.

- `INSERT INTO u SELECT ... FROM t` was written too late to the binary log if t was very frequently updated during the execution of this query. This could cause a problem with `mysqlbinlog` or replication. The master must be upgraded, not the slave. (Bug#136)

- Fixed checking of random part of `WHERE` clause. (Bug#142)

- Fixed a bug with multiple-table updates with `InnoDB` tables. This bug occurred as, in many cases, `InnoDB` tables cannot be updated ``on the fly,'' but offsets to the records have to be stored in a temporary table.

- Added missing file `mysql_secure_installation` to the `server` RPM subpackage. (Bug#141)

- Fixed MySQL (and `myisamchk`) crash on artificially corrupted `.MYI` files.

- Don't allow `BACKUP TABLE` to overwrite existing files.

- Fixed a bug with multiple-table `UPDATE` statements when user had all privileges on the database where tables are located and there were any entries in `tables_priv` table, that is, `grant_option` was true.

- Fixed a bug that allowed a user with table or column grants on some table, `TRUNCATE` any table in the same database.

- Fixed deadlock when doing `LOCK TABLE` followed by `DROP TABLE` in the same thread. In this case one could still kill the thread with `KILL`.

- `LOAD DATA LOCAL INFILE` was not properly written to the binary log (hence not properly replicated). (Bug#82)

- `RAND()` entries were not read correctly by `mysqlbinlog` from the binary log which caused problems when restoring a table that was inserted with `RAND()`. `INSERT INTO t1 VALUES(RAND())`. In replication this worked ok.

- `SET SQL_LOG_BIN=0` was ignored for `INSERT DELAYED` queries. (Bug#104)

- `SHOW SLAVE STATUS` reported too old positions (columns `Relay_Master_Log_File` and `Exec_Master_Log_Pos`) for the last executed statement from the master, if this statement was the `COMMIT` of a transaction. The master must be upgraded for that, not the slave. (Bug#52)

- `LOAD DATA INFILE` was not replicated by the slave if `replicate_*_table` was set on the slave. (Bug#86)

- After `RESET SLAVE`, the coordinates displayed by `SHOW SLAVE STATUS` looked un-reset (though they were, but only internally). (Bug#70)

- Fixed query cache invalidation on `LOAD DATA`.

- Fixed memory leak on `ANALYZE` procedure with error.

- Fixed a bug in handling `CHAR(0)` columns that could cause incorrect results from the query.

- Fixed rare bug with incorrect initialization of `AUTO_INCREMENT` column, as a secondary column in a multi-column key (see Section 3.6.9, « Utiliser `AUTO_INCREMENT` »), when data was inserted with `INSERT ... SELECT` or `LOAD DATA` into an empty table.

- On Windows, `STOP SLAVE` didn't stop the slave until the slave got one new command from the master (this bug has been fixed for MySQL 4.0.11 by releasing updated 4.0.11a Windows packages, which include this individual fix on top of the 4.0.11 sources). (Bug#69)

- Fixed a crash when no database was selected and `LOAD DATA` command was issued with full table name specified, including database prefix.

- Fixed a crash when shutting down replication on some platforms (for example, Mac OS X).

- Fixed a portability bug with `pthread_attr_getstacksize` on HP-UX 10.20 (Patch was also included in 4.0.11a sources).

- Fixed the `bigint` test to not fail on some platforms (for example, HP-UX and Tru64) due to different return values of the `atof()` function.

- Fixed the `rpl_rotate_logs` test to not fail on certain platforms (e.g. Mac OS X) due to a too long file name (changed `slave-master-info.opt` to `.slave-mi`).

### C.3.15. Changements de la version 4.0.11 (20 Février 2003)

Fonctionnalité ajoutée ou modifiée :

- `NULL` is now sorted LAST if you use `ORDER BY ... DESC` (as it was before MySQL 4.0.2). This change was required to comply with the SQL-99 standard. (The original change was made because we thought that SQL-99 required `NULL` to be always sorted at the same position, but this was incorrect).

- Added `START TRANSACTION` (SQL-99 syntax) as alias for `BEGIN`. This is recommended to use instead of `BEGIN` to start a transaction.

- Added `OLD_PASSWORD()` as a synonym for `PASSWORD()`.

- Allow keyword `ALL` in group functions.

- Added support for some new `INNER JOIN` and `JOIN` syntaxes. For example, `SELECT * FROM t1 INNER JOIN t2` didn't work before.

- Novell NetWare 6.0 porting effort completed, Novell patches merged into the main source tree.

Bogues corrigés :

- Fixed problem with multiple-table delete and `InnoDB` tables.

- Fixed a problem with `BLOB NOT NULL` columns used with `IS NULL`.

- Re-added missing pre- and post(un)install scripts to the Linux RPM packages (they were missing after the renaming of the server subpackage).

- Fixed that table locks are not released with multiple-table updates and deletes with `InnoDB` storage engine.

- Fixed bug in updating `BLOB` columns with long strings.

- Fixed integer-wraparound when giving big integer (>= 10 digits) to function that requires an unsigned argument, like `CREATE TABLE (...) AUTO_INCREMENT=#`.

- `MIN(key_column)` could in some cases return `NULL` on a column with `NULL` and other values.

- `MIN(key_column)` and `MAX(key_column)` could in some cases return incorrect values when used in `OUTER JOIN`.

- `MIN(key_column)` and `MAX(key_column)` could return incorrect values if one of the tables was empty.

- Fixed rare crash in compressed MyISAM tables with blobs.

- Fixed bug in using aggregate functions as argument for `INTERVAL`, `CASE`, `FIELD`, `CONCAT_WS`, `ELT` and `MAKE_SET` functions.

- When running with `--lower-case-table-names` (default on Windows) and you had tables or databases with mixed case on disk, then executing `SHOW TABLE STATUS` followed with `DROP DATABASE` or `DROP TABLE` could fail with `Errcode 13`.

### C.3.16. Changements de la version 4.0.10 (29 janvier 2003)

Fonctionnalité ajoutée ou modifiée :

- Added option `--log-error[=file_name]` to `mysqld_safe` and `mysqld`. This option will force all error messages to be put in a log file if the option `--console` is not given. On Windows `--log-error` is enabled as default, with a default name of `host_name.err` if the name is not specified.

- Changed some things from `Warning:` to `Note:` in the log files.

- The mysqld server should now compile on NetWare.

- Added optimization that if one does `GROUP BY ... ORDER BY NULL` then result is not sorted.

- New `--ft-stopword-file` command-line option for `mysqld` to replace/disable the built-in stopword list that is used in full-text searches. See Section 13.5.3.18, « Syntaxe de `SHOW VARIABLES` ».

- Changed default stack size from 64K to 192K; This fixes a core dump problem on Red Hat 8.0 and other systems with a `glibc` that requires a stack size larger than 128K for `gethostbyaddr()` to resolve a hostname. You can fix this for earlier MySQL versions by starting `mysqld` with `--thread-stack=192K`.

- Added `mysql_waitpid` to the binary distribution and the `MySQL-client` RPM subpackage (required for `mysql-test-run`).

- Renamed the main MySQL RPM package to `MySQL-server`. When updating from an older version, `MySQL-server.rpm` will simply replace `MySQL.rpm`.

- If a slave is configured with `replicate_wild_do_table=db.%` or `replicate_wild_ignore_table=db.%`, these rules will be applied to `CREATE/DROP DATABASE`, too.

- Added timeout value for `MASTER_POS_WAIT()`.

Bogues corrigés :

- Fixed initialization of the random seed for newly created threads to give a better `rand()` distribution from the first call.

- Fixed a bug that caused `mysqld` to hang when a table was opened with the `HANDLER` command and then dropped without being closed.

- Fixed bug in logging to binary log (which affects replication) a query that inserts a `NULL` in an `AUTO_INCREMENT` column and also uses `LAST_INSERT_ID()`.

- Fixed an unlikely bug that could cause a memory overrun when using `ORDER BY constant_expression`.

- Fixed a table corruption in `myisamchk`'s parallel repair mode.

- Fixed bug in query cache invalidation on simple table renaming.

- Fixed bug in `mysqladmin --relative`.

- On some 64-bit systems, `show status` reported a strange number for `Open_files` and `Open_streams`.

- Fixed incorrect number of columns in `EXPLAIN` on empty table.

- Fixed bug in `LEFT JOIN` that caused zero rows to be returned in the case the `WHERE` condition was evaluated as `FALSE` after reading `const` tables. (Unlikely condition).

- `FLUSH PRIVILEGES` didn't correctly flush table/column privileges when `mysql.tables_priv` is empty.

- Fixed bug in replication when using `LOAD DATA INFILE` one a file that updated an `AUTO_INCREMENT` column with `NULL` or `0`. This bug only affected MySQL 4.0 masters (not slaves or MySQL 3.23 masters). Note: If you have a slave that has replicated a file with generated `AUTO_INCREMENT` columns then the slave data is corrupted and you should reinitialize the affected tables from the master.

- Fixed possible memory overrun when sending a `BLOB` value larger than 16M to the client.

- Fixed incorrect error message when setting a `NOT NULL` column to an expression that returned `NULL`.

- Fixed core dump bug in `str LIKE "%other_str%"` where `str` or `other_str` contained characters >= 128.

- Fixed bug: When executing on master `LOAD DATA` and `InnoDB` failed with `table full` error the binary log was corrupted.

### C.3.17. Changements de la version 4.0.9 (09 janvier 2003)

Fonctionnalité ajoutée ou modifiée :

- `OPTIMIZE TABLE` will for MyISAM tables treat all `NULL` values as different when calculating cardinality. This helps in optimizing joins between tables where one of the tables has a lot of `NULL` values in a indexed column:

      SELECT * from t1,t2 where t1.a=t2.key_with_a_lot_of_null;

- Added join operator `FORCE INDEX (key_list)`. This acts likes `USE INDEX (key_list)` but with the addition that a table scan is assumed to be VERY expensive. One bad thing with this is that it makes `FORCE` a reserved word.

- Reset internal row buffer in MyISAM after each query. This will reduce memory in the case you have a lot of big blobs in a table.

Bogues corrigés :

- A security patch in 4.0.8 causes the mysqld server to die if the remote hostname can't be resolved. This is now fixed.

- Fixed crash when replication big `LOAD DATA INFILE` statement that caused log rotation.

### C.3.18. Changements de la version 4.0.8 (07 janvier 2003)

Fonctionnalité ajoutée ou modifiée :

- Default `max_packet_length` for libmysqld.c is now 1024*1024*1024.

- One can now specify `max_allowed_packet` in a file ready by `mysql_options(MYSQL_READ_DEFAULT_FILE)`. for clients.

- When sending a too big packet to the server with the not compressed protocol, the client now gets an error message instead of a lost connection.

- We now send big queries/result rows in bigger hunks, which should give a small speed improvement.

- Fixed some bugs with the compressed protocol for rows > 16M.

- `InnoDB` tables now also support `ON UPDATE CASCADE` in `FOREIGN KEY` constraints. See the `InnoDB` section in the manual for the `InnoDB` changelog.

Bogues corrigés :

- Fixed bug in `ALTER TABLE` with BDB tables.

- Fixed core dump bug in `QUOTE()` function.

- Fixed a bug in handling communication packets bigger than 16M. Unfortunately this required a protocol change; If you upgrade the server to 4.0.8 and above and have clients that uses packets >= 255*255*255 bytes (=16581375) you must also upgrade your clients to at least 4.0.8. If you don't upgrade, the clients will hang when sending a big packet.

- Fixed bug when sending blobs longer than 16M to client.

- Fixed bug in `GROUP BY` when used on BLOB column with `NULL` values.

- Fixed a bug in handling `NULL` values in `CASE` ... WHEN ...

### C.3.19. Changements de la version 4.0.7 (20 Décembre 2002)

Fonctionnalité ajoutée ou modifiée :

- `mysqlbug` now also reports the compiler version used for building the binaries (if the compiler supports the option `--version`).

Bogues corrigés :

- Fixed compilation problems on OpenUnix and HPUX 10.20.

- Fixed some optimization problems when compiling MySQL with `-DBIG_TABLES` on a 32-bit system.

- `mysql_drop_db()` didn't check permissions properly so anyone could drop another users database. `DROP DATABASE` is checked properly.

### C.3.20. Changements de la version 4.0.6 (14 Décembre 2002 : Gamma)

Fonctionnalité ajoutée ou modifiée :

- Added syntax support for `CHARACTER SET xxx` and `CHARSET=xxx` table options (to be able to read table dumps from 4.1).

- Fixed replication bug that caused the slave to loose its position in some cases when the replication log was rotated.

- Fixed that a slave will restart from the start of a transaction if it's killed in the middle of one.

- Moved the manual pages from `man` to `man/man1` in the binary distributions.

- The default type returned by `IFNULL(A,B)` is now set to be the more 'general' of the types of `A` and `B`. (The order is `STRING`, `REAL` or `INTEGER`).

- Moved the `mysql.server` startup script in the RPM packages from `/etc/rc.d/init.d/mysql` to `/etc/init.d/mysql` (which almost all current Linux distributions support for LSB compliance).

- Added `Qcache_lowmem_prunes` status variable (number of queries that were deleted from cache because of low memory).

- Fixed `mysqlcheck` so it can deal with table names containing dashes.

- Bulk insert optimization (see Section 13.5.3.18, « Syntaxe de `SHOW VARIABLES` ») is no longer used when inserting small (less than 100) number of rows.

- Optimization added for queries like `SELECT ... FROM merge_table WHERE indexed_column=constant_expr`.

- Added functions `LOCALTIME` and `LOCALTIMESTAMP` as synonyms for `NOW()`.

- `CEIL` is now an alias for `CEILING`.

- The `CURRENT_USER()` function can be used to get a `user@host` value as it was matched in the `GRANT` system. See Section 12.8.4, « Fonctions diverses ».

- Fixed `CHECK` constraints to be compatible with SQL-99. This made `CHECK` a reserved word. (Checking of `CHECK` constraints is still not implemented).

- Added `CAST(... as CHAR)`.

- Added PostgreSQL compatible `LIMIT` syntax: `SELECT ... LIMIT row_count OFFSET offset`

- `mysql_change_user()` will now reset the connection to the state of a fresh connect (Ie, `ROLLBACK` any active transaction, close all temporary tables, reset all user variables etc..)

- `CHANGE MASTER` and `RESET SLAVE` now require that slave threads be both already stopped; these commands will return an error if at least one of these two threads is running.

Bogues corrigés :

- Fixed number of found rows returned in `multi table updates`

- Make `--lower-case-table-names` default on Mac OS X as the default file system (HFS+) is case insensitive. See Section 9.2.2, « Sensibilité à la casse pour les noms ».

- Transactions in `AUTOCOMMIT=0` mode didn't rotate binary log.

- A fix for the bug in a `SELECT` with joined tables with `ORDER BY` and `LIMIT` clause when filesort had to be used. In that case `LIMIT` was applied to filesort of one of the tables, although it could not be. This fix also solved problems with `LEFT JOIN`.

- `mysql_server_init()` now makes a copy of all arguments. This fixes a problem when using the embedded server in C# program.

- Fixed buffer overrun in `libmysqlclient` library that allowed a malicious MySQL server to crash the client application.

- Fixed security-related bug in `mysql_change_user()` handling. All users are strongly recommended to upgrade to version 4.0.6.

- Fixed bug that prevented `--chroot` command-line option of `mysqld` from working.

- Fixed bug in phrase operator `"..."` in boolean full-text search.

- Fixed bug that caused `OPTIMIZE TABLE` to corrupt the table under some rare circumstances.

- Part rewrite of multiple-table-update to optimize it, make it safer and more bug free.

- `LOCK TABLES` now works together with multiple-table-update and multiple-table-delete.

- `--replicate-do=xxx` didn't work for `UPDATE` commands. (Bug introduced in 4.0.0)

- Fixed shutdown problem on Mac OS X.

- Major `InnoDB` bugs in `REPLACE, AUTO_INCREMENT, INSERT INTO ... SELECT ...` were fixed. See the `InnoDB` changelog in the `InnoDB` section of the manual.

- `RESET SLAVE` caused a crash if the slave threads were running.

### C.3.21. Changements de la version 4.0.5 (13 novembre 2002)

Fonctionnalité ajoutée ou modifiée :

- Port number was added to host name (if it is known) in `SHOW PROCESSLIST` command

- Changed handling of last argument in `WEEK()` so that one can get week number according to the ISO 8601 specification. (Old code should still work).

- Fixed that `INSERT DELAYED` threads don't hang on `Waiting for INSERT` when one sends a `SIGHUP` to `mysqld`.

- Change that `AND` works according to SQL-99 when it comes to `NULL` handling. In practice, this only affects queries where you do something like `WHERE ... NOT (NULL AND 0)`.

- `mysqld` will now resolve `basedir` to its full path (with `realpath()`). This enables one to use relative symlinks to the MySQL installation directory. This will however cause `show variables` to report different directories on systems where there is a symbolic link in the path.

- Fixed that MySQL will not use index scan on index disabled with `IGNORE INDEX` or `USE INDEX`. to be ignored.

- Added `--use-frm` option to `mysqlcheck`. When used with `REPAIR`, it gets the table structure from the `.frm` file, so the table can be repaired even if the `.MYI` header is corrupted.

- Fixed bug in `MAX()` optimization when used with `JOIN` and `ON` expressions.

- Added support for reading of MySQL 4.1 table definition files.

- `BETWEEN` behavior changed (see Section 12.1.3, « Opérateurs de comparaison »). Now `datetime_col BETWEEN timestamp AND timestamp` should work as expected.

- One can create `TEMPORARY` `MERGE` tables now.

- `DELETE FROM myisam_table` now shrinks not only the `.MYD` file but also the `.MYI` file.

- When one uses the `--open-files-limit=#` option to `mysqld_safe` it's now passed on to `mysqld`.

- Changed output from `EXPLAIN` from `'where used'` to `'Using where'` to make it more in line with other output.

- Removed variable `safe_show_database` as it was no longer used.

- Updated source tree to be built using `automake 1.5` and `libtool 1.4`.

- Fixed an inadvertently changed option (`--ignore-space`) back to the original `--ignore-spaces` in `mysqlclient`. (Both syntaxes will work).

- Don't require `UPDATE` privilege when using `REPLACE`.

- Added support for `DROP TEMPORARY TABLE ...`, to be used to make replication safer.

- When transactions are enabled, all commands that update temporary tables inside a `BEGIN/COMMIT` are now stored in the binary log on `COMMIT` and not stored if one does `ROLLBACK`. This fixes some problems with non-transactional temporary tables used inside transactions.

- Allow braces in joins in all positions. Formerly, things like `SELECT * FROM (t2 LEFT JOIN t3 USING (a)), t1` worked, but not `SELECT * FROM t1, (t2 LEFT JOIN t3 USING (a))`. Note that braces are simply removed, they do not change the way the join is executed.

- `InnoDB` now supports also isolation levels `READ UNCOMMITTED` and `READ COMMITTED`. For a detailed `InnoDB` changelog, see Section C.9, « Evolutions de InnoDB » in this manual.

Bogues corrigés :

- Fixed bug in `MAX()` optimization when used with `JOIN` and `ON` expressions.

- Fixed that `INSERT DELAY` threads don't hang on `Waiting for INSERT` when one sends a `SIGHUP` to `mysqld`.

- Fixed that MySQL will not use an index scan on an index that has been disabled with `IGNORE INDEX` or `USE INDEX`.

- Corrected test for `root` user in `mysqld_safe`.

- Fixed error message issued when storage engine cannot do `CHECK` or `REPAIR`.

- Fixed rare core dump problem in complicated `GROUP BY` queries that didn't return any result.

- Fixed `mysqlshow` to work properly with wildcarded database names and with database names that contain underscores.

- Portability fixes to get MySQL to compile cleanly with Sun Forte 5.0.

- Fixed `MyISAM` crash when using dynamic-row tables with huge numbers of packed fields.

- Fixed query cache behavior with `BDB` transactions.

- Fixed possible floating point exception in `MATCH` relevance calculations.

- Fixed bug in full-text search `IN BOOLEAN MODE` that made `MATCH` to return incorrect relevance value in some complex joins.

- Fixed a bug that limited `MyISAM` key length to a value slightly less that 500. It is exactly 500 now.

- Fixed that `GROUP BY` on columns that may have a `NULL` value doesn't always use disk based temporary tables.

- The filename argument for the `--des-key-file` argument to `mysqld` is interpreted relative to the data directory if given as a relative pathname.

- Removed a condition that temp table with index on column that can be `NULL` has to be `MyISAM`. This was okay for 3.23, but not needed in 4.*. This resulted in slowdown in many queries since 4.0.2.

- Small code improvement in multiple-table updates.

- Fixed a newly introduced bug that caused `ORDER BY ... LIMIT row_count` to not return all rows.

- Fixed a bug in multiple-table deletes when outer join is used on an empty table, which gets first to be deleted.

- Fixed a bug in multiple-table updates when a single table is updated.

- Fixed bug that caused `REPAIR TABLE` and `myisamchk` to corrupt `FULLTEXT` indexes.

- Fixed bug with caching the `mysql` grant table database. Now queries in this database are not cached in the query cache.

- Small fix in `mysqld_safe` for some shells.

- Give error if a `MyISAM` `MERGE` table has more than 2 ^ 32 rows and MySQL was not compiled with `-DBIG_TABLES`.

- Fixed some `ORDER BY ... DESC` problems with `InnoDB` tables.

### C.3.22. Changements de la version 4.0.4 (29 septembre 2002)

- Fixed bug where `GRANT`/`REVOKE` failed if hostname was given in non-matching case.

- Don't give warning in `LOAD DATA INFILE` when setting a `timestamp` to a string value of `'0'`.

- Fixed bug in `myisamchk -R` mode.

- Fixed bug that caused `mysqld` to crash on `REVOKE`.

- Fixed bug in `ORDER BY` when there is a constant in the `SELECT` statement.

- One didn't get an error message if `mysqld` couldn't open the privilege tables.

- `SET PASSWORD FOR ...` closed the connection in case of errors (bug from 4.0.3).

- Increased max possible `max_allowed_packet` in `mysqld` to 1 GB.

- Fixed bug when doing a multi-line `INSERT` on a table with an `AUTO_INCREMENT` key which was not in the first part of the key.

- Changed `LOAD DATA INFILE` to not recreate index if the table had rows from before.

- Fixed overrun bug when calling `AES_DECRYPT()` with incorrect arguments.

- `--skip-ssl` can now be used to disable SSL in the MySQL clients, even if one is using other SSL options in an option file or previously on the command line.

- Fixed bug in `MATCH ... AGAINST( ... IN BOOLEAN MODE)` used with `ORDER BY`.

- Added `LOCK TABLES` and `CREATE TEMPORARY TABLES` privilege on the database level. One must run the `mysql_fix_privilege_tables` script on old installations to activate these.

- In `SHOW TABLE ... STATUS`, compressed tables sometimes showed up as `dynamic`.

- `SELECT @@[global|session].var_name` didn't report `global | session` in the result column name.

- Fixed problem in replication that `FLUSH LOGS` in a circular replication setup created an infinite number of binary log files. Now a `rotate-binary-log` command in the binary log will not cause slaves to rotate logs.

- Removed `STOP EVENT` from binary log when doing `FLUSH LOGS`.

- Disable the use of `SHOW NEW MASTER FOR SLAVE` as this needs to be completely reworked in a future release.

- Fixed a bug with constant expression (for example, field of a one-row table, or field from a table, referenced by a `UNIQUE` key) appeared in `ORDER BY` part of `SELECT DISTINCT`.

- `--log-binary=a.b.c` now properly strips off `.b.c`.

- `FLUSH LOGS` removed numerical extension for all future update logs.

- `GRANT ... REQUIRE` didn't store the SSL information in the `mysql.user` table if SSL was not enabled in the server.

- `GRANT ... REQUIRE NONE` can now be used to remove SSL information.

- `AND` is now optional between `REQUIRE` options.

- `REQUIRE` option was not properly saved, which could cause strange output in `SHOW GRANTS`.

- Fixed that `mysqld --help` reports correct values for `--datadir` and `--bind-address`.

- Fixed that one can drop UDFs that didn't exist when `mysqld` was started.

- Fixed core dump problem with `SHOW VARIABLES` on some 64-bit systems (like Solaris SPARC).

- Fixed a bug in `my_getopt()`; `--set-variable` syntax didn't work for those options that didn't have a valid variable in the `my_option` struct. This affected at least the `default-table-type` option.

- Fixed a bug from 4.0.2 that caused `REPAIR TABLE` and `myisamchk --recover` to fail on tables with duplicates in a unique key.

- Fixed a bug from 4.0.3 in calculating the default datatype for some functions. This affected queries of type `CREATE TABLE table_name SELECT expression(),...`

- Fixed bug in queries of type `SELECT * FROM table-list GROUP BY ...` and `SELECT DISTINCT * FROM ...`.

- Fixed bug with the `--slow-log` when logging an administrator command (like `FLUSH TABLES`).

- Fixed a bug that `OPTIMIZE` of locked and modified table, reported table corruption.

- Fixed a bug in `my_getopt()` in handling of special prefixes (`--skip-`, `--enable-`). `--skip-external-locking` didn't work and the bug may have affected other similar options.

- Fixed bug in checking for output file name of the `tee` option.

- Added some more optimization to use index for `SELECT ... FROM many_tables .. ORDER BY key limit #`

- Fixed problem in `SHOW OPEN TABLES` when a user didn't have access permissions to one of the opened tables.

### C.3.23. Changements de la version 4.0.3 (26 Août 2002 : Beta)

- Fixed problem with types of user variables. (Bug#551)

- Fixed problem with `configure ... --localstatedir=...`.

- Cleaned up `mysql.server` script.

- Fixed a bug in `mysqladmin shutdown` when pid file was modified while `mysqladmin` was still waiting for the previous one to disappear. This could happen during a very quick restart and caused `mysqladmin` to hang until `shutdown_timeout` seconds had passed.

- Don't increment warnings when setting `AUTO_INCREMENT` columns to `NULL` in `LOAD DATA INFILE`.

- Fixed all boolean type variables/options to work with the old syntax, for example, all of these work: `--lower-case-table-names`, `--lower-case-table-names=1`, `-O lower-case-table-names=1`, `--set-variable=lower-case-table-names=1`

- Fixed shutdown problem (SIGTERM signal handling) on Solaris. (Bug from 4.0.2).

- `SHOW MASTER STATUS` now returns an empty set if binary log is not enabled.

- `SHOW SLAVE STATUS` now returns an empty set if slave is not initialized.

- Don't update MyISAM index file on update if not strictly necessary.

- Fixed bug in `SELECT DISTINCT ... FROM many_tables ORDER BY not-used-column`.

- Fixed a bug with `BIGINT` values and quoted strings.

- Added `QUOTE()` function that performs SQL quoting to produce values that can be used as data values in queries.

- Changed variable `DELAY_KEY_WRITE` to an enum to allow one set `DELAY_KEY_WRITE` for all tables without taking down the server.

- Changed behavior of `IF(condition,column,NULL)` so that it returns the value of the column type.

- Made `safe_mysqld` a symlink to `mysqld_safe` in binary distribution.

- Fixed security bug when having an empty database name in the `user.db` table.

- Fixed some problems with `CREATE TABLE ... SELECT function()`.

- `mysqld` now has the option `--temp-pool` enabled by default as this gives better performance with some operating systems.

- Fixed problem with too many allocated alarms on slave when connecting to master many times (normally not a very critical error).

- Fixed hang in `CHANGE MASTER TO` if the slave thread died very quickly.

- Big cleanup in replication code (less logging, better error messages, etc..)

- If the `--code-file` option is specified, the server calls `setrlimit()` to set the maximum allowed core file size to unlimited, so core files can be generated.

- Fixed bug in query cache after temporary table creation.

- Added `--count=N` (`-c`) option to `mysqladmin`, to make the program do only `N` iterations. To be used with `--sleep` (`-i`). Useful in scripts.

- Fixed bug in multiple-table `UPDATE`: when updating a table, `do_select()` became confused about reading records from a cache.

- Fixed bug in multiple-table `UPDATE` when several fields were referenced from a single table

- Fixed bug in truncating nonexisting table.

- Fixed bug in `REVOKE` that caused user resources to be randomly set.

- Fixed bug in `GRANT` for the new `CREATE TEMPORARY TABLE` privilege.

- Fixed bug in multiple-table `DELETE` when tables are re-ordered in the table initialization method and ref_lengths are of different sizes.

- Fixed two bugs in `SELECT DISTINCT` with large tables.

- Fixed bug in query cache initialization with very small query cache size.

- Allow `DEFAULT` with `INSERT` statement.

- The startup parameters `myisam_max_sort_file_size` and `myisam_max_extra_sort_file_size` are now given in bytes, not megabytes.

- External system locking of `MyISAM`/`ISAM` files is now turned off by default. One can turn this on with `--external-locking`. (For most users this is never needed).

- Fixed core dump bug with `INSERT ... SET db_name.table_name.colname=''`.

- Fixed client hangup bug when using some SQL commands with incorrect syntax.

- Fixed a timing bug in `DROP DATABASE`

- New `SET [GLOBAL | SESSION]` syntax to change thread-specific and global server variables at runtime.

- Added variable `slave_compressed_protocol`.

- Renamed variable `query_cache_startup_type` to `query_cache_type`, `myisam_bulk_insert_tree_size` to `bulk_insert_buffer_size`, `record_buffer` to `read_buffer_size` and `record_rnd_buffer` to `read_rnd_buffer_size`.

- Renamed some SQL variables, but old names will still work until 5.0. See Section 2.6.3, « Passer de la version 3.23 à la version 4.0 ».

- Renamed `--skip-locking` to `--skip-external-locking`.

- Removed unused variable `query_buffer_size`.

- Fixed a bug that made the pager option in the `mysql` client non-functional.

- Added full `AUTO_INCREMENT` support to `MERGE` tables.

- Extended `LOG()` function to accept an optional arbitrary base parameter. See Section 12.4.2, « Fonctions mathématiques ».

- Added `LOG2()` function (useful for finding out how many bits a number would require for storage).

- Added `LN()` natural logarithm function for compatibility with other databases. It is synonymous with `LOG(X)`.

### C.3.24. Changements de la version 4.0.2 (01 Juillet 2002)

- Cleaned up `NULL` handling for default values in `DESCRIBE table_name`.

- Fixed `truncate()` to round up negative values to the nearest integer.

- Changed `--chroot=path` option to execute `chroot()` immediately after all options have been parsed.

- Don't allow database names that contain ‘`\`’.

- `lower_case_table_names` now also affects database names.

- Added `XOR` operator (logical and bitwise `XOR`) with `^` as a synonym for bitwise `XOR`.

- Added function `IS_FREE_LOCK("lock_name")`. Based on code contributed by Hartmut Holzgraefe `<hartmut@six.de>`.

- Removed `mysql_ssl_clear()` from C API, as it was not needed.

- `DECIMAL` and `NUMERIC` types can now read exponential numbers.

- Added `SHA1()` function to calculate 160 bit hash value as described in RFC 3174 (Secure Hash Algorithm). This function can be considered a cryptographically more secure equivalent of `MD5()`. See Section 12.8.4, « Fonctions diverses ».

- Added `AES_ENCRYPT()` and `AES_DECRYPT()` functions to perform encryption according to AES standard (Rijndael). See Section 12.8.4, « Fonctions diverses ».

- Added `--single-transaction` option to `mysqldump`, allowing a consistent dump of `InnoDB` tables. See Section 8.8, « `mysqldump`, sauvegarde des structures de tables et les données ».

- Fixed bug in `innodb_log_group_home_dir` in `SHOW VARIABLES`.

- Fixed a bug in optimizer with merge tables when non-unique values are used in summing up (causing crashes).

- Fixed a bug in optimizer when a range specified makes index grouping impossible (causing crashes).

- Fixed a rare bug when `FULLTEXT` index is present and no tables are used.

- Added privileges `CREATE TEMPORARY TABLES`, `EXECUTE`, `LOCK TABLES`, `REPLICATION CLIENT`, `REPLICATION SLAVE`, `SHOW DATABASES` and `SUPER`. To use these, you must have run the `mysql_fix_privilege_tables` script after upgrading.

- Fixed query cache align data bug.

- Fixed mutex bug in replication when reading from master fails.

- Added missing mutex in `TRUNCATE TABLE`; This fixes some core dump/hangup problems when using `TRUNCATE TABLE`.

- Fixed bug in multiple-table `DELETE` when optimizer uses only indexes.

- Fixed that `ALTER TABLE table_name RENAME new_table_name` is as fast as `RENAME TABLE`.

- Fixed bug in `GROUP BY` with two or more fields, where at least one field can contain `NULL` values.

- Use `Turbo Boyer-Moore` algorithm to speed up `LIKE "%keyword%"` searches.

- Fixed bug in `DROP DATABASE` with symlink.

- Fixed crash in `REPAIR ... USE_FRM`.

- Fixed bug in `EXPLAIN` with `LIMIT offset != 0`.

- Fixed bug in phrase operator `"..."` in boolean full-text search.

- Fixed bug that caused duplicated rows when using truncation operator `*` in boolean full-text search.

- Fixed bug in truncation operator of boolean full-text search (incorrect results when there are only `+word*`s in the query).

- Fixed bug in boolean full-text search that caused a crash when an identical `MATCH` expression that did not use an index appeared twice.

- Query cache is now automatically disabled in `mysqldump`.

- Fixed problem on Windows 98 that made sending of results very slow.

- Boolean full-text search weighting scheme changed to something more reasonable.

- Fixed bug in boolean full-text search that caused MySQL to ignore queries of `ft_min_word_len` characters.

- Boolean full-text search now supports ``phrase searches''.

- New configure option `--without-query-cache`.

- Memory allocation strategy for ``root memory'' changed. Block size now grows with number of allocated blocks.

- `INET_NTOA()` now returns `NULL` if you give it an argument that is too large (greater than the value corresponding to `255.255.255.255`).

- Fix `SQL_CALC_FOUND_ROWS` to work with `UNION`. It will work only if the first `SELECT` has this option and if there is global `LIMIT` for the entire statement. For the moment, this requires using parentheses for individual `SELECT` queries within the statement.

- Fixed bug in `SQL_CALC_FOUND_ROWS` and `LIMIT`.

- Don't give an error for `CREATE TABLE ...(... VARCHAR(0))`.

- Fixed `SIGINT` and `SIGQUIT` problems in `mysql.cc` on Linux with some `glibc` versions.

- Fixed bug in `convert.cc`, which is caused by having an incorrect `net_store_length()` linked in the `CONVERT::store()` method.

- `DOUBLE` and `FLOAT` columns now honor the `UNSIGNED` flag on storage.

- `InnoDB` now retains foreign key constraints through `ALTER TABLE` and `CREATE/DROP INDEX`.

- `InnoDB` now allows foreign key constraints to be added through the `ALTER TABLE` syntax.

- `InnoDB` tables can now be set to automatically grow in size (autoextend).

- Added `--ignore-lines=n` option to `mysqlimport`. This has the same effect as the `IGNORE n LINES` clause for `LOAD DATA`.

- Fixed bug in `UNION` with last offset being transposed to total result set.

- `REPAIR ... USE_FRM` added.

- Fixed that `DEFAULT_SELECT_LIMIT` is always imposed on `UNION` result set.

- Fixed that some `SELECT` options can appear only in the first `SELECT`.

- Fixed bug with `LIMIT` with `UNION`, where last select is in the braces.

- Fixed that full-text works fine with `UNION` operations.

- Fixed bug with indexless boolean full-text search.

- Fixed bug that sometimes appeared when full-text search was used with `const` tables.

- Fixed incorrect error value when doing a `SELECT` with an empty `HEAP` table.

- Use `ORDER BY column DESC` now sorts `NULL` values first. (In other words, `NULL` values sort first in all cases, whether or not `DESC` is specified.) This is changed back in 4.0.10.

- Fixed bug in `WHERE key_name='constant' ORDER BY key_name DESC`.

- Fixed bug in `SELECT DISTINCT ... ORDER BY DESC` optimization.

- Fixed bug in `... HAVING 'GROUP_FUNCTION'(xxx) IS [NOT] NULL`.

- Fixed bug in truncation operator for boolean full-text search.

- Allow value of `--user=#` option for `mysqld` to be specified as a numeric user ID.

- Fixed a bug where `SQL_CALC_ROWS` returned an incorrect value when used with one table and `ORDER BY` and with `InnoDB` tables.

- Fixed that `SELECT 0 LIMIT 0` doesn't hang thread.

- Fixed some problems with `USE/IGNORE INDEX` when using many keys with the same start column.

- Don't use table scan with `BerkeleyDB` and `InnoDB` tables when we can use an index that covers the whole row.

- Optimized `InnoDB` sort-buffer handling to take less memory.

- Fixed bug in multiple-table `DELETE` and `InnoDB` tables.

- Fixed problem with `TRUNCATE` and `InnoDB` tables that produced the error `Can't execute the given command because you have active locked tables or an active transaction`.

- Added `NO_UNSIGNED_SUBTRACTION` to the set of flags that may be specified with the `--sql-mode` option for `mysqld`. It disables unsigned arithmetic rules when it comes to subtraction. (This will make MySQL 4.0 behave more like 3.23 with `UNSIGNED` columns).

- The result returned for all bit functions (`|`, `<<`, ...) is now of type `unsigned integer`.

- Added detection of `nan` values in `MyISAM` to make it possible to repair tables with `nan` in float or double columns.

- Fixed new bug in `myisamchk` where it didn't correctly update number of ``parts'' in the `MyISAM` index file.

- Changed to use `autoconf` 2.52 (from `autoconf` 2.13).

- Fixed optimization problem where the MySQL Server was in ``preparing'' state for a long time when selecting from an empty table which had contained a lot of rows.

- Fixed bug in complicated join with `const` tables. This fix also improves performance a bit when referring to another table from a `const` table.

- First pre-version of multiple-table `UPDATE` statement.

- Fixed bug in multiple-table `DELETE`.

- Fixed bug in `SELECT CONCAT(argument_list) ... GROUP BY 1`.

- `INSERT ... SELECT` did a full rollback in case of an error. Fixed so that we only roll back the last statement in the current transaction.

- Fixed bug with empty expression for boolean full-text search.

- Fixed core dump bug in updating full-text key from/to `NULL`.

- ODBC compatibility: Added `BIT_LENGTH()` function.

- Fixed core dump bug in `GROUP BY BINARY column`.

- Added support for `NULL` keys in `HEAP` tables.

- Use index for `ORDER BY` in queries of type: `SELECT * FROM t WHERE key_part1=1 ORDER BY key_part1 DESC,key_part2 DESC`

- Fixed bug in `FLUSH QUERY CACHE`.

- Added `CAST()` and `CONVERT()` functions. The `CAST` and `CONVERT` functions are nearly identical and mainly useful when you want to create a column with a specific type in a `CREATE ... SELECT` statement. For more information, read Section 12.7, « Fonctions de transtypage ».

- `CREATE ... SELECT` on `DATE` and `TIME` functions now create columns of the expected type.

- Changed order in which keys are created in tables.

- Added new columns `Null` and `Index_type` to `SHOW INDEX` output.

- Added `--no-beep` and `--prompt` options to `mysql` command-line client.

- New feature: management of user resources.

      GRANT ... WITH MAX_QUERIES_PER_HOUR N1
                     MAX_UPDATES_PER_HOUR N2
                     MAX_CONNECTIONS_PER_HOUR N3;

  See Section 5.6.4, « Limiter les ressources utilisateurs ».

- Added `mysql_secure_installation` to the `scripts/` directory.

### C.3.25. Changements de la version 4.0.1 (23 décembre 2001)

- Added `system` command to `mysql`.

- Fixed bug when `HANDLER` was used with some unsupported table type.

- `mysqldump` now puts `ALTER TABLE tbl_name DISABLE KEYS` and `ALTER TABLE tbl_name ENABLE KEYS` in the sql dump.

- Added `mysql_fix_extensions` script.

- Fixed stack overrun problem with `LOAD DATA FROM MASTER` on OSF/1.

- Fixed shutdown problem on HP-UX.

- Added `DES_ENCRYPT()` and `DES_DECRYPT()` functions.

- Added `FLUSH DES_KEY_FILE` statement.

- Added `--des-key-file` option to `mysqld`.

- `HEX(string)` now returns the characters in `string` converted to hexadecimal.

- Fixed problem with `GRANT` when using `lower_case_table_names=1`.

- Changed `SELECT ... IN SHARE MODE` to `SELECT ... LOCK IN SHARE MODE` (as in MySQL 3.23).

- A new query cache to cache results from identical `SELECT` queries.

- Fixed core dump bug on 64-bit machines when it got an incorrect communication packet.

- `MATCH ... AGAINST(... IN BOOLEAN MODE)` can now work without `FULLTEXT` index.

- Fixed slave to replicate from 3.23 master.

- Miscellaneous replication fixes/cleanup.

- Got shutdown to work on Mac OS X.

- Added `myisam/ft_dump` utility for low-level inspection of `FULLTEXT` indexes.

- Fixed bug in `DELETE ... WHERE ... MATCH ...`.

- Added support for `MATCH ... AGAINST(... IN BOOLEAN MODE)`. Note: you must rebuild your tables with `ALTER TABLE tablename TYPE=MyISAM` to be able to use boolean full-text search.

- `LOCATE()` and `INSTR()` are now case-sensitive if either argument is a binary string.

- Changed `RAND()` initialization so that `RAND(N)` and `RAND(N+1)` are more distinct.

- Fixed core dump bug in `UPDATE ... ORDER BY`.

- In 3.23, `INSERT INTO ... SELECT` always had `IGNORE` enabled. Now MySQL will stop (and possibly roll back) by default in case of an error unless you specify `IGNORE`.

- Ignore `DATA DIRECTORY` and `INDEX DIRECTORY` directives on Windows.

- Added boolean full-text search code. It should be considered early alpha.

- Extended `MODIFY` and `CHANGE` in `ALTER TABLE` to accept the `FIRST` and `AFTER` keywords.

- Indexes are now used with `ORDER BY` on a whole `InnoDB` table.

### C.3.26. Changements de la version 4.0.0 (Octobre 2001 : alpha)

- Added `--xml` option to `mysql` for producing XML output.

- Added full-text variables `ft_min_word_len`, `ft_max_word_len`, and `ft_max_word_len_for_sort` system variables.

- Added full-text variables `ft_min_word_len`, `ft_max_word_len`, and `ft_max_word_len_for_sort` variables to `myisamchk`.

- Added documentation for `libmysqld`, the embedded MySQL server library. Also added example programs (a `mysql` client and `mysqltest` test program) which use `libmysqld`.

- Removed all Gemini hooks from MySQL server.

- Removed `my_thread_init()` and `my_thread_end()` from `mysql_com.h`, and added `mysql_thread_init()` and `mysql_thread_end()` to `mysql.h`.

- Support for communication packets > 16MB. In 4.0.1 we will extend `MyISAM` to be able to handle these.

- Secure connections (with SSL).

- Unsigned `BIGINT` constants now work. `MIN()` and `MAX()` now handle signed and unsigned `BIGINT` numbers correctly.

- New character set `latin1_de` which provides correct German sorting.

- `STRCMP()` now uses the current character set when doing comparisons, which means that the default comparison behavior now is case insensitive.

- `TRUNCATE TABLE` and `DELETE FROM tbl_name` are now separate functions. One bonus is that `DELETE FROM tbl_name` now returns the number of deleted rows, rather than zero.

- `DROP DATABASE` now executes a `DROP TABLE` on all tables in the database, which fixes a problem with `InnoDB` tables.

- Added support for `UNION`.

- Added support for multiple-table `DELETE` operations.

- A new `HANDLER` interface to `MyISAM` tables.

- Added support for `INSERT` on `MERGE` tables. Patch from Benjamin Pflugmann.

- Changed `WEEK(date,0)` to match the calendar in the USA.

- `COUNT(DISTINCT)` is about 30% faster.

- Speed up all internal list handling.

- Speed up `IS NULL`, `ISNULL()` and some other internal primitives.

- Full-text index creation now is much faster.

- Tree-like cache to speed up bulk inserts and `myisam_bulk_insert_tree_size` variable.

- Searching on packed (`CHAR`/`VARCHAR`) keys is now much faster.

- Optimized queries of type: `SELECT DISTINCT * from tbl_name ORDER by key_part1 LIMIT row_count`.

- `SHOW CREATE TABLE` now shows all table attributes.

- `ORDER BY ... DESC` can now use keys.

- `LOAD DATA FROM MASTER` ``automatically'' sets up a slave.

- Renamed `safe_mysqld` to `mysqld_safe` to make this name more in line with other MySQL scripts/commands.

- Added support for symbolic links to `MyISAM` tables. Symlink handling is now enabled by default for Windows.

- Added `SQL_CALC_FOUND_ROWS` and `FOUND_ROWS()`. This makes it possible to know how many rows a query would have returned without a `LIMIT` clause.

- Changed output format of `SHOW OPEN TABLES`.

- Allow `SELECT expression LIMIT ...`.

- Added `ORDER BY` syntax to `UPDATE` and `DELETE`.

- `SHOW INDEXES` is now a synonym for `SHOW INDEX`.

- Added `ALTER TABLE tbl_name DISABLE KEYS` and `ALTER TABLE tbl_name ENABLE KEYS` commands.

- Allow use of `IN` as a synonym for `FROM` in `SHOW` commands.

- Implemented ``repair by sort'' for `FULLTEXT` indexes. `REPAIR TABLE`, `ALTER TABLE`, and `OPTIMIZE TABLE` for tables with `FULLTEXT` indexes are now up to 100 times faster.

- Allow standard SQL syntax `X'hexadecimal-number'`.

- Cleaned up global lock handling for `FLUSH TABLES WITH READ LOCK`.

- Fixed problem with `DATETIME = constant` in `WHERE` optimization.

- Added `--master-data` and `--no-autocommit` options to `mysqldump`. (Thanks to Brian Aker for this.)

- Added script `mysql_explain_log.sh` to distribution. (Thanks to mobile.de).

## C.4. Changements de la version 3.23.x (Recent; still supported)

Please note that since release 4.0 is now production level, only critical fixes are done in the 3.23 release series. You are recommended to upgrade when possible, to take advantage of all speed and feature improvements in 4.0. See Section 2.6.3, « Passer de la version 3.23 à la version 4.0 ».

The 3.23 release has several major features that are not present in previous versions. We have added three new table types:

- `MyISAM`

  A new ISAM library which is tuned for SQL and supports large files.

- `InnoDB`

  A transaction-safe storage engine that supports row level locking, and many Oracle-like features.

- `BerkeleyDB` or `BDB`

  Uses the Berkeley DB library from Sleepycat Software to implement transaction-safe tables.

Note that only `MyISAM` is available in the standard binary distribution.

The 3.23 release also includes support for database replication between a master and many slaves, full-text indexing, and much more.

All new features are being developed in the 4.x version. Only bug fixes and minor enhancements to existing features will be added to 3.23.

The replication code and BerkeleyDB code is still not as tested and as the rest of the code, so we will probably need to do a couple of future releases of 3.23 with small fixes for this part of the code. As long as you don't use these features, you should be quite safe with MySQL 3.23!

Note that the above doesn't mean that replication or Berkeley DB don't work. We have done a lot of testing of all code, including replication and `BDB` without finding any problems. It only means that not as many users use this code as the rest of the code and because of this we are not yet 100% confident in this code.

### C.4.1. Changements de la version 3.23.59 (not released yet)

- Fixed a symlink vulnerability in `mysqlbug` script - vulnerability id CAN-2004-0381. (Bug#3284)

- Fixed bug in privilege checking of `ALTER TABLE RENAME`. (Bug#3270)

- Fixed bugs in `ACOS()`, `ASIN()` (Bug#2338) and in `FLOOR()` (Bug#3051). The cause of the problem is an overly strong optimization done by `gcc` in this case.

- Fixed bug in `INSERT ... SELECT` statements where, if a `NOT NULL` column is assigned a value of `NULL`, the following columns in the row might be assigned a value of zero. (Bug#2012)

- If a query was ignored on the slave (because of `replicate-ignore-table` and other similar rules), the slave still checked if the query got the same error code (0, no error) as on the master. So if the master had an error on the query (for example, ``Duplicate entry'' in a multiple-row insert), then the slave stopped and warned that the error codes didn't match. This is a backport of the fix for MySQL 4.0. (Bug#797)

- `mysqlbinlog` now asks for a password at console when the `-p/--password` option is used with no argument. This is how the other clients (`mysqladmin`, `mysqldump`..) already behave. Note that one now has to use `mysqlbinlog -p<my_password>`; `mysqlbinlog -p <my_password>` will not work anymore (in other words, put no space after `-p`). (Bug#1595)

- On some 64-bit machines (some HP-UX and Solaris machines), a slave installed with the 64-bit MySQL binary could not connect to its master (it connected to itself instead). (Bug#1256, Bug#1381)

- Fixed a Windows-specific bug present since MySQL 3.23.57 and 3.23.58 that caused Windows slaves to crash when they started replication if a `master.info` file existed. (Bug#1720)

- Fixed bug in `ALTER TABLE RENAME`, when rename to the table with the same name in another database silently dropped destination table if it existed. (Bug#2628)

### C.4.2. Changements de la version 3.23.58 (11 septembre 2003)

- Fixed buffer overflow in password handling which could potentially be exploited by MySQL users with `ALTER` privilege on the `mysql.user` table to execute random code or to gain shell access with the UID of the mysqld process (thanks to Jedi/Sector One for spotting and reporting this bug).

- `mysqldump` now correctly quotes all identifiers when communicating with the server. This assures that during the dump process, `mysqldump` will never send queries to the server that result in a syntax error. This problem is not related to the `mysqldump` program's output, which was not changed. (Bug#1148)

- Fixed table/column grant handling - proper sort order (from most specific to less specific, see Section 5.5.6, « Contrôle d'accès, étape 2 : Vérification de la requête ») was not honored. (Bug#928)

- Fixed overflow bug in `MyISAM` and `ISAM` when a row is updated in a table with a large number of columns and at least one `BLOB/TEXT` column.

- Fixed MySQL so that field length (in C API) for the second column in `SHOW CREATE TABLE` is always larger than the data length. The only known application that was affected by the old behavior was Borland dbExpress, which truncated the output from the command. (Bug#1064)

- Fixed `ISAM` bug in `MAX()` optimization.

- Fixed `Unknown error` when doing `ORDER BY` on reference table which was used with `NULL` value on `NOT NULL` column. (Bug#479)

### C.4.3. Changements de la version 3.23.57 (06 juin 2003)

- Fixed problem in alarm handling that could cause problems when getting a packet that is too large.

- Fixed problem when installing MySQL as a service on Windows when one gave 2 arguments (option file group name and service name) to `mysqld`.

- Fixed `kill pid-of-mysqld` to work on Mac OS X.

- `SHOW TABLE STATUS` displayed incorrect `Row_format` value for tables that have been compressed with `myisampack`. (Bug#427)

- `SHOW VARIABLES LIKE 'innodb_data_file_path'` displayed only the name of the first datafile. (Bug#468)

- Fixed security problem where `mysqld` didn't allow one to `UPDATE` rows in a table even if one had a global `UPDATE` privilege and a database `SELECT` privilege.

- Fixed a security problem with `SELECT` and wildcarded select list, when user only had partial column `SELECT` privileges on the table.

- Fixed unlikely problem in optimizing `WHERE` clause with a constant expression such as in `WHERE 1 AND (a=1 AND b=1)`.

- Fixed problem on IA-64 with timestamps that caused `mysqlbinlog` to fail.

- The default option for `innodb_flush_log_at_trx_commit` was changed from 0 to 1 to make `InnoDB` tables ACID by default. See Section 15.5, « Options de démarrage `InnoDB` ».

- Fixed problem with too many allocated alarms on slave when connecting to master many times (normally not a very critical error).

- Fixed a bug in replication of temporary tables. (Bug#183)

- Fixed 64-bit bug that affected at least AMD hammer systems.

- Fixed a bug when doing `LOAD DATA INFILE IGNORE`: When reading the binary log, `mysqlbinlog` and the replication code read `REPLACE` instead of `IGNORE`. This could make the slave's table become different from the master's table. (Bug#218)

- Fixed overflow bug in `MyISAM` when a row is inserted into a table with a large number of columns and at least one `BLOB/TEXT` column. Bug was caused by incorrect calculation of the needed buffer to pack data.

- The binary log was not locked during `TRUNCATE table_name` or `DELETE FROM table_name` statements, which could cause an `INSERT` to `table_name` to be written to the log before the `TRUNCATE` or `DELETE` statements.

- Fixed rare bug in `UPDATE` of `InnoDB` tables where one row could be updated multiple times.

- Produce an error for empty table and column names.

- Changed `PROCEDURE ANALYSE()` to report `DATE` instead of `NEWDATE`.

- Changed `PROCEDURE ANALYSE(#)` to restrict the number of values in an `ENUM` column to `#` also for string values.

- `mysqldump` no longer silently deletes the binary logs when invoked with the `--master-data` or `--first-slave` option; while this behavior was convenient for some users, others may suffer from it. Now one has to explicitly ask for binary logs to be deleted by using the new `--delete-master-logs` option.

- Fixed a bug in `mysqldump` when it was invoked with the `--master-data` option: The `CHANGE MASTER TO` statements that were appended to the SQL dump had incorrect coordinates. (Bug#159)

### C.4.4. Changements de la version 3.23.56 (13 mars 2003)

- Fixed `mysqld` crash on extremely small values of `sort_buffer` variable.

- Fixed a bug in privilege system for `GRANT UPDATE` on column level.

- Fixed a rare bug when using a date in `HAVING` with `GROUP BY`.

- Fixed checking of random part of `WHERE` clause. (Bug#142)

- Fixed MySQL (and `myisamchk`) crash on artificially corrupted `.MYI` files.

- Security enhancement: `mysqld` no longer reads options from world-writeable config files.

- Security enhancement: `mysqld` and `safe_mysqld` now only use the first `--user` option specified on the command line. (Normally this comes from `/etc/my.cnf`)

- Security enhancement: Don't allow `BACKUP TABLE` to overwrite existing files.

- Fixed unlikely deadlock bug when one thread did a `LOCK TABLE` and another thread did a `DROP TABLE`. In this case one could do a `KILL` on one of the threads to resolve the deadlock.

- `LOAD DATA INFILE` was not replicated by slave if `replicate_*_table` was set on the slave.

- Fixed a bug in handling `CHAR(0)` columns that could cause incorrect results from the query.

- Fixed a bug in `SHOW VARIABLES` on 64-bit platforms. The bug was caused by incorrect declaration of variable `server_id`.

- The Comment column in `SHOW TABLE STATUS` now reports that it can contain `NULL` values (which is the case for a crashed `.frm` file).

- Fixed the `rpl_rotate_logs` test to not fail on certain platforms (e.g. Mac OS X) due to a too long file name (changed `slave-master-info.opt` to `.slave-mi`).

- Fixed a problem with `BLOB NOT NULL` columns used with `IS NULL`.

- Fixed bug in `MAX()` optimization in `MERGE` tables.

- Better `RAND()` initialization for new connections.

- Fixed bug with connect timeout. This bug was manifested on OS's with `poll()` system call, which resulted in timeout the value specified as it was executed in both `select()` and `poll()`.

- Fixed bug in `SELECT * FROM table WHERE datetime1 IS NULL OR datetime2 IS NULL`.

- Fixed bug in using aggregate functions as argument for `INTERVAL`, `CASE`, `FIELD`, `CONCAT_WS`, `ELT` and `MAKE_SET` functions.

- When running with `--lower-case-table-names` (default on Windows) and you had tables or databases with mixed case on disk, then executing `SHOW TABLE STATUS` followed with `DROP DATABASE` or `DROP TABLE` could fail with `Errcode 13`.

- Fixed bug in logging to binary log (which affects replication) a query that inserts a `NULL` in an `auto_increment` field and also uses `LAST_INSERT_ID()`.

- Fixed bug in `mysqladmin --relative`.

- On some 64-bit systems, `show status` reported a strange number for `Open_files` and `Open_streams`.

### C.4.5. Changements de la version 3.23.55 (23 janvier 2003)

- Fixed double `free`'d pointer bug in `mysql_change_user()` handling, that enabled a specially hacked version of MySQL client to crash `mysqld`. Note, that one needs to login to the server by using a valid user account to be able to exploit this bug.

- Fixed bug with the `--slow-log` when logging an administrator command (like `FLUSH TABLES`).

- Fixed bug in `GROUP BY` when used on BLOB column with `NULL` values.

- Fixed a bug in handling `NULL` values in `CASE ... WHEN ...`.

- Bugfix for `--chroot` (see Section C.4.6, « Changements de la version 3.23.54 (05 décembre 2002) ») is reverted. Unfortunately, there is no way to make it to work, without introducing backward-incompatible changes in `my.cnf`. Those who need `--chroot` functionality, should upgrade to MySQL 4.0. (The fix in the 4.0 branch did not break backward-compatibility).

- Make `--lower-case-table-names` default on Mac OS X as the default file system (HFS+) is case insensitive.

- Fixed a bug in `scripts/mysqld_safe.sh` in `NOHUP_NICENESS` testing.

- Transactions in `AUTOCOMMIT=0` mode didn't rotate binary log.

- Fixed a bug in `scripts/make_binary_distribution` that resulted in a remaining `@HOSTNAME@` variable instead of replacing it with the correct path to the `hostname` binary.

- Fixed a very unlikely bug that could cause `SHOW PROCESSLIST` to core dump in pthread_mutex_unlock() if a new thread was connecting.

- Forbid `SLAVE STOP` if the thread executing the query has locked tables. This removes a possible deadlock situation.

### C.4.6. Changements de la version 3.23.54 (05 décembre 2002)

- Fixed a bug, that allowed to crash `mysqld` with a specially crafted packet.

- Fixed a rare crash (double `free`'d pointer) when altering a temporary table.

- Fixed buffer overrun in `libmysqlclient` library that allowed malicious MySQL server to crash the client application.

- Fixed security-related bug in `mysql_change_user()` handling. All users are strongly recommended to upgrade to the version 3.23.54.

- Fixed bug that prevented `--chroot` command-line option of `mysqld` from working.

- Fixed bug that made `OPTIMIZE TABLE` to corrupt the table under some rare circumstances.

- Fixed `mysqlcheck` so it can deal with table names containing dashes.

- Fixed shutdown problem on Mac OS X.

- Fixed bug with comparing an indexed `NULL` field with `<=> NULL`.

- Fixed bug that caused `IGNORE INDEX` and `USE INDEX` sometimes to be ignored.

- Fixed rare core dump problem in complicated `GROUP BY` queries that didn't return any result.

- Fixed a bug where `MATCH ... AGAINST () >=0` was treated as if it was `>`.

- Fixed core dump in `SHOW PROCESSLIST` when running with an active slave (unlikely timing bug).

- Make it possible to use multiple MySQL servers on Windows (code backported from 4.0.2).

- One can create `TEMPORARY` `MERGE` tables now.

- Fixed that `--core-file` works on Linux (at least on kernel 2.4.18).

- Fixed a problem with `BDB` and `ALTER TABLE`.

- Fixed reference to freed memory when doing complicated `GROUP BY ... ORDER BY` queries. Symptom was that `mysqld` died in function `send_fields`.

- Allocate heap rows in smaller blocks to get better memory usage.

- Fixed memory allocation bug when storing `BLOB` values in internal temporary tables used for some (unlikely) `GROUP BY` queries.

- Fixed a bug in key optimizing handling where the expression `WHERE column_name = key_column_name` was calculated as true for `NULL` values.

- Fixed core dump bug when doing `LEFT JOIN ... WHERE key_column=NULL`.

- Fixed `MyISAM` crash when using dynamic-row tables with huge numbers of packed fields.

- Updated source tree to be built using `automake 1.5` and `libtool 1.4`.

### C.4.7. Changements de la version 3.23.53 (09 octobre 2002)

- Fixed crash when `SHOW INNODB STATUS` was used and `skip-innodb` was defined.

- Fixed possible memory corruption bug in binary log file handling when slave rotated the logs (only affected 3.23, not 4.0).

- Fixed problem in `LOCK TABLES` on Windows when one connects to a database that contains upper case letters.

- Fixed that `--skip-show-databases` doesn't reset the `--port` option.

- Small fix in `safe_mysqld` for some shells.

- Fixed that `FLUSH STATUS` doesn't reset `delayed_insert_threads`.

- Fixed core dump bug when using the `BINARY` cast on a `NULL` value.

- Fixed race condition when someone did a `GRANT` at the same time a new user logged in or did a `USE database`.

- Fixed bug in `ALTER TABLE` and `RENAME TABLE` when running with `-O lower_case_table_names=1` (typically on Windows) when giving the table name in uppercase.

- Fixed that `-O lower_case_table_names=1` also converts database names to lower case.

- Fixed unlikely core dump with `SELECT ... ORDER BY ... LIMIT`.

- Changed `AND/OR` to report that they can return NULL. This fixes a bug in `GROUP BY` on `AND/OR` expressions that return `NULL`.

- Fixed a bug that `OPTIMIZE` of locked and modified MyISAM table, reported table corruption.

- Fixed a `BDB`-related `ALTER TABLE` bug with dropping a column and shutting down immediately thereafter.

- Fixed problem with `configure ... --localstatedir=...`.

- Fixed problem with `UNSIGNED BIGINT` on AIX (again).

- Fixed bug in pthread_mutex_trylock() on HPUX 11.0.

- Multi-threaded stress tests for `InnoDB`.

### C.4.8. Changements de la version 3.23.52 (14 août 2002)

- Wrap `BEGIN`/`COMMIT` around transaction in the binary log. This makes replication honor transactions.

- Fixed security bug when having an empty database name in the `user.db` table.

- Changed initialization of `RND()` to make it less predicatable.

- Fixed problem with `GROUP BY` on result with expression that created a `BLOB` field.

- Fixed problem with `GROUP BY` on columns that have `NULL` values. To solve this we now create an `MyISAM` temporary table when doing a `GROUP BY` on a possible `NULL` item. From MySQL 4.0.5 we can use in memory `HEAP` tables for this case.

- Fixed problem with privilege tables when downgrading from 4.0.2 to 3.23.

- Fixed thread bug in `SLAVE START`, `SLAVE STOP` and automatic repair of MyISAM tables that could cause table cache to be corrupted.

- Fixed possible thread related key-cache-corruption problem with `OPTIMIZE TABLE` and `REPAIR TABLE`.

- Added name of 'administrator command' logs.

- Fixed bug with creating an auto-increment value on second part of a `UNIQUE()` key where first part could contain `NULL` values.

- Don't write slave-timeout reconnects to the error log.

- Fixed bug with slave net read timeouting

- Fixed a core-dump bug with `MERGE` tables and `MAX()` function.

- Fixed bug in `ALTER TABLE` with `BDB` tables.

- Fixed bug when logging `LOAD DATA INFILE` to binary log with no active database.

- Fixed a bug in range optimizer (causing crashes).

- Fixed possible problem in replication when doing `DROP DATABASE` on a database with `InnoDB` tables.

- Fixed `mysql_info()` to return 0 for `Duplicates` value when using `INSERT DELAYED IGNORE`.

- Added `-DHAVE_BROKEN_REALPATH` to the Mac OS X (darwin) compile options in `configure.in` to fix a failure under high load.

### C.4.9. Changements de la version 3.23.51 (31 mai 2002)

- Fix bug with closing tags missing slash for `mysqldump` XML output.

- Remove end space from `ENUM` values. (This fixed a problem with `SHOW CREATE TABLE`.)

- Fixed bug in `CONCAT_WS()` that cut the result.

- Changed name of server variables `Com_show_master_stat` to `Com_show_master_status` and `Com_show_slave_stat` to `Com_show_slave_status`.

- Changed handling of `gethostbyname()` to make the client library thread-safe even if `gethostbyname_r` doesn't exist.

- Fixed core-dump problem when giving a wrong password string to `GRANT`.

- Fixed bug in `DROP DATABASE` with symlinked directory.

- Fixed optimization problem with `DATETIME` and value outside `DATETIME` range.

- Removed Sleepycat's `BDB` doc files from the source tree, as they're not needed (MySQL covers `BDB` in its own documentation).

- Fixed MIT-pthreads to compile with `glibc` 2.2 (needed for `make dist`).

- Fixed the `FLOAT(X+1,X)` is not converted to `FLOAT(X+2,X)`. (This also affected `DECIMAL`, `DOUBLE` and `REAL` types)

- Fixed the result from `IF()` is case in-sensitive if the second and third arguments are case sensitive.

- Fixed core dump problem on OSF/1 in `gethostbyname_r`.

- Fixed that underflowed decimal fields are not zero filled.

- If we get an overflow when inserting `'+11111'` for `DECIMAL(5,0) UNSIGNED` columns, we will just drop the sign.

- Fixed optimization bug with `ISNULL(expression_which_cannot_be_null)` and `ISNULL(constant_expression)`.

- Fixed host lookup bug in the `glibc` library that we used with the 3.23.50 Linux-x86 binaries.

### C.4.10. Changements de la version 3.23.50 (21 avril 2002)

- Fixed buffer overflow problem if someone specified a too long datadir parameter to mysqld

- Add missing `<row>` tags for `mysqldump` XML output.

- Fixed problem with `crash-me` and `gcc` 3.0.4.

- Fixed that `@@unknown_variable` doesn't hang server.

- Added `@@VERSION` as a synonym for `VERSION()`.

- `SHOW VARIABLES LIKE 'xxx'` is now case-insensitive.

- Fixed timeout for `GET_LOCK()` on HP-UX with DCE threads.

- Fixed memory allocation bug in the `glibc` library used to build Linux binaries, which caused mysqld to die in 'free()'.

- Fixed `SIGINT` and `SIGQUIT` problems in `mysql`.

- Fixed bug in character table converts when used with big ( > 64K) strings.

- `InnoDB` now retains foreign key constraints through `ALTER TABLE` and `CREATE/DROP INDEX`.

- `InnoDB` now allows foreign key constraints to be added through the `ALTER TABLE` syntax.

- `InnoDB` tables can now be set to automatically grow in size (autoextend).

- Our Linux RPMS and binaries are now compiled with `gcc` 3.0.4, which should make them a bit faster.

- Fixed some buffer overflow problems when reading startup parameters.

- Because of problems on shutdown we have now disabled named pipes on Windows by default. One can enable named pipes by starting mysqld with `--enable-named-pipe`.

- Fixed bug when using `WHERE key_column = 'J' or key_column='j'`.

- Fixed core-dump bug when using `--log-bin` with `LOAD DATA INFILE` without an active database.

- Fixed bug in `RENAME TABLE` when used with `lower_case_table_names=1` (default on Windows).

- Fixed unlikely core-dump bug when using `DROP TABLE` on a table that was in use by a thread that also used queries on only temporary tables.

- Fixed problem with `SHOW CREATE TABLE` and `PRIMARY KEY` when using 32 indexes.

- Fixed that one can use `SET PASSWORD` for the anonymous user.

- Fixed core dump bug when reading client groups from option files using `mysql_options()`.

- Memory leak (16 bytes per every corrupted table) closed.

- Fixed binary builds to use `--enable-local-infile`.

- Update source to work with new version of `bison`.

- Updated shell scripts to now agree with new POSIX standard.

- Fixed bug where `DATE_FORMAT()` returned empty string when used with `GROUP BY`.

### C.4.11. Changements de la version 3.23.49

- For a `MERGE` table, `DELETE FROM merge_table` used without a `WHERE` clause no longer clears the mapping for the table by emptying the `.MRG` file. Instead, it deletes records from the mapped tables.

- Don't give warning for a statement that is only a comment; this is needed for `mysqldump --disable-keys` to work.

- Fixed unlikely caching bug when doing a join without keys. In this case, the last used field for a table always returned `NULL`.

- Added options to make `LOAD DATA LOCAL INFILE` more secure.

- MySQL binary release 3.23.48 for Linux contained a new `glibc` library, which has serious problems under high load and Red Hat 7.2. The 3.23.49 binary release doesn't have this problem.

- Fixed shutdown problem on NT.

### C.4.12. Changements de la version 3.23.48 (07 février 2002)

- Added `--xml` option to `mysqldump` for producing XML output.

- Changed to use `autoconf` 2.52 (from `autoconf` 2.13)

- Fixed bug in complicated join with `const` tables.

- Added internal safety checks for `InnoDB`.

- Some `InnoDB` variables were always shown in `SHOW VARIABLES` as `OFF` on high-byte-first systems (like SPARC).

- Fixed problem with one thread using an `InnoDB` table and another thread doing an `ALTER TABLE` on the same table. Before that, `mysqld` could crash with an assertion failure in `row0row.c`, line 474.

- Tuned the `InnoDB` SQL optimizer to favor index searches more often over table scans.

- Fixed a performance problem with `InnoDB` tables when several large `SELECT` queries are run concurrently on a multiprocessor Linux computer. Large CPU-bound `SELECT` queries will now also generally run faster on all platforms.

- If MySQL binlogging is used, `InnoDB` now prints after crash recovery the latest MySQL binlog name and the offset `InnoDB` was able to recover to. This is useful, for example, when resynchronizing a master and a slave database in replication.

- Added better error messages to help in installation problems of `InnoDB` tables.

- It is now possible to recover MySQL temporary tables that have become orphaned inside the `InnoDB` tablespace.

- `InnoDB` now prevents a `FOREIGN KEY` declaration where the signedness is not the same in the referencing and referenced integer columns.

- Calling `SHOW CREATE TABLE` or `SHOW TABLE STATUS` could cause memory corruption and make `mysqld` crash. Especially at risk was `mysqldump`, because it frequently calls `SHOW CREATE TABLE`.

- If inserts to several tables containing an `AUTO_INCREMENT` column were wrapped inside one `LOCK TABLES`, `InnoDB` asserted in `lock0lock.c`.

- In 3.23.47 we allowed several `NULL` values in a `UNIQUE` secondary index for an `InnoDB` table. But `CHECK TABLE` was not relaxed: it reports the table as corrupt. `CHECK TABLE` no longer complains in this situation.

- `SHOW GRANTS` now shows `REFERENCES` instead of `REFERENCE`.

### C.4.13. Changements de la version 3.23.47 (27 décembre 2001)

- Fixed bug when using the following construct: `SELECT ... WHERE key=@var_name OR key=@var_name2`

- Restrict `InnoDB` keys to 500 bytes.

- `InnoDB` now supports `NULL` in keys.

- Fixed shutdown problem on HP-UX. (Introduced in 3.23.46)

- Fixed core dump bug in replication when using `SELECT RELEASE_LOCK()`.

- Added new command: `DO expression,[expression]`

- Added `slave-skip-errors` option.

- Added statistics variables for all MySQL commands. (`SHOW STATUS` is now much longer.)

- Fixed default values for `InnoDB` tables.

- Fixed that `GROUP BY expr DESC` works.

- Fixed bug when using `t1 LEFT JOIN t2 ON t2.key=constant`.

- `mysql_config` now also works with binary (relocated) distributions.

### C.4.14. Changements de la version 3.23.46 (29 novembre 2001)

- Fixed problem with aliased temporary table replication.

- `InnoDB` and `BDB` tables will now use index when doing an `ORDER BY` on the whole table.

- Fixed bug where one got an empty set instead of a DEADLOCK error when using `BDB` tables.

- One can now kill `ANALYZE`, `REPAIR`, and `OPTIMIZE TABLE` when the thread is waiting to get a lock on the table.

- Fixed race condition in `ANALYZE TABLE`.

- Fixed bug when joining with caching (unlikely to happen).

- Fixed race condition when using the binary log and `INSERT DELAYED` which could cause the binary log to have rows that were not yet written to `MyISAM` tables.

- Changed caching of binary log to make replication slightly faster.

- Fixed bug in replication on Mac OS X.

### C.4.15. Changements de la version 3.23.45 (22 novembre 2001)

- `(UPDATE|DELETE) ...WHERE MATCH` bugfix.

- shutdown should now work on Darwin (Mac OS X).

- Fixed core dump when repairing corrupted packed `MyISAM` files.

- `--core-file` now works on Solaris.

- Fix a bug which could cause `InnoDB` to complain if it cannot find free blocks from the buffer cache during recovery.

- Fixed bug in `InnoDB` insert buffer `B-tree` handling that could cause crashes.

- Fixed bug in `InnoDB` lock timeout handling.

- Fixed core dump bug in `ALTER TABLE` on a `TEMPORARY` `InnoDB` table.

- Fixed bug in `OPTIMIZE TABLE` that reset index cardinality if it was up to date.

- Fixed problem with `t1 LEFT_JOIN t2 ... WHERE t2.date_column IS NULL` when date_column was declared as `NOT NULL`.

- Fixed bug with `BDB` tables and keys on `BLOB` columns.

- Fixed bug in `MERGE` tables on OS with 32-bit file pointers.

- Fixed bug in `TIME_TO_SEC()` when using negative values.

### C.4.16. Changements de la version 3.23.44 (31 octobre 2001)

- Fixed `Rows_examined` count in slow query log.

- Fixed bug when using a reference to an `AVG()` column in `HAVING`.

- Fixed that date functions that require correct dates, like `DAYOFYEAR(column)`, will return `NULL` for `0000-00-00` dates.

- Fixed bug in const-propagation when comparing columns of different types. (`SELECT * FROM date_col="2001-01-01" and date_col=time_col`)

- Fixed bug that caused error message `Can't write, because of unique constraint` with some `GROUP BY` queries.

- Fixed problem with `sjis` character strings used within quoted table names.

- Fixed core dump when using `CREATE ... FULLTEXT` keys with other storage engines than `MyISAM`.

- Don't use `signal()` on Windows because this appears to not be 100% reliable.

- Fixed bug when doing `WHERE col_name=NULL` on an indexed column that had `NULL` values.

- Fixed bug when doing `LEFT JOIN ... ON (col_name = constant) WHERE col_name = constant`.

- When using replications, aborted queries that contained `%` could cause a core dump.

- `TCP_NODELAY` was not used on some systems. (Speed problem.)

- Applied portability fixes for OS/2. (Patch by Yuri Dario.)

The following changes are for `InnoDB` tables:

- Add missing `InnoDB` variables to `SHOW VARIABLES`.

- Foreign keys checking is now done for `InnoDB` tables.

- `DROP DATABASE` now works also for `InnoDB` tables.

- `InnoDB` now supports datafiles and raw disk partitions bigger than 4 GB on those operating systems that have big files.

- `InnoDB` calculates better table cardinality estimates for the MySQL optimizer.

- Accent characters in the default character set `latin1` are ordered according to the MySQL ordering.

  Note: if you are using `latin1` and have inserted characters whose code is greater than 127 into an indexed `CHAR` column, you should run `CHECK TABLE` on your table when you upgrade to 3.23.44, and drop and reimport the table if `CHECK TABLE` reports an error!

- A new `my.cnf` parameter, `innodb_thread_concurrency`, helps in performance tuning in heavily concurrent environments.

- A new `my.cnf` parameter, `innodb_fast_shutdown`, speeds up server shutdown.

- A new `my.cnf` parameter, `innodb_force_recovery`, helps to save your data in case the disk image of the database becomes corrupt.

- `innodb_monitor` has been improved and a new `innodb_table_monitor` added.

- Increased maximum key length from 500 to 7000 bytes.

- Fixed a bug in replication of `AUTO_INCREMENT` columns with multiple-line inserts.

- Fixed a bug when the case of letters changes in an update of an indexed secondary column.

- Fixed a hang when there are > 24 datafiles.

- Fixed a crash when `MAX(col)` is selected from an empty table, and `col` is not the first column in a multi-column index.

- Fixed a bug in purge which could cause crashes.

### C.4.17. Changements de la version 3.23.43 (04 octobre 2001)

- Fixed a bug in `INSERT DELAYED` and `FLUSH TABLES` introduced in 3.23.42.

- Fixed unlikely bug, which returned non-matching rows, in `SELECT` with many tables and multi-column indexes and 'range' type.

- Fixed an unlikely core dump bug when doing `EXPLAIN SELECT` when using many tables and `ORDER BY`.

- Fixed bug in `LOAD DATA FROM MASTER` when using table with `CHECKSUM=1`.

- Added unique error message when one gets a DEADLOCK during a transaction with `BDB` tables.

- Fixed problem with `BDB` tables and `UNIQUE` columns defined as `NULL`.

- Fixed problem with `myisampack` when using pre-space filled `CHAR` columns.

- Applied patch from Yuri Dario for OS/2.

- Fixed bug in `--safe-user-create`.

### C.4.18. Changements de la version 3.23.42 (08 septembre 2001)

- Fixed problem when using `LOCK TABLES` and `BDB` tables.

- Fixed problem with `REPAIR TABLE` on `MyISAM` tables with row lengths in the range from 65517 to 65520 bytes.

- Fixed rare hang when doing `mysqladmin shutdown` when there was a lot of activity in other threads.

- Fixed problem with `INSERT DELAYED` where delayed thread could be hanging on `upgrading locks` for no apparent reason.

- Fixed problem with `myisampack` and `BLOB`.

- Fixed problem when one edited `.MRG` tables by hand. (Patch from Benjamin Pflugmann).

- Enforce that all tables in a `MERGE` table come from the same database.

- Fixed bug with `LOAD DATA INFILE` and transactional tables.

- Fix bug when using `INSERT DELAYED` with wrong column definition.

- Fixed core dump during `REPAIR` of some particularly broken tables.

- Fixed bug in `InnoDB` and `AUTO_INCREMENT` columns.

- Fixed bug in `InnoDB` and `RENAME TABLE` columns.

- Fixed critical bug in `InnoDB` and `BLOB` columns. If you have used `BLOB` columns larger than 8000 bytes in an `InnoDB` table, it is necessary to dump the table with `mysqldump`, drop it and restore it from the dump.

- Applied large patch for OS/2 from Yuri Dario.

- Fixed problem with `InnoDB` when one could get the error `Can't execute the given command...` even when no transaction was active.

- Applied some minor fixes that concern Gemini.

- Use real arithmetic operations even in integer context if not all arguments are integers. (Fixes uncommon bug in some integer contexts).

- Don't force everything to lowercase on Windows. (To fix problem with Windows and `ALTER TABLE`). Now `--lower_case_names` also works on Unix.

- Fixed that automatic rollback is done when thread end doesn't lock other threads.

### C.4.19. Changements de la version 3.23.41 (11 août 2001)

- Added `--sql-mode=value[,value[,value]]` option to `mysqld`. See Section 4.3.1, « Options de ligne de commande de `mysqld` ».

- Fixed possible problem with `shutdown` on Solaris where the `.pid` file wasn't deleted.

- `InnoDB` now supports < 4 GB rows. The former limit was 8000 bytes.

- The `doublewrite` file flush method is used in `InnoDB`. It reduces the need for Unix `fsync()` calls to a fraction and improves performance on most Unix flavors.

- You can now use the `InnoDB` Monitor to print a lot of `InnoDB` state information, including locks, to the standard output. This is useful in performance tuning.

- Several bugs which could cause hangs in `InnoDB` have been fixed.

- Split `record_buffer` to `record_buffer` and `record_rnd_buffer`. To make things compatible to previous MySQL versions, if `record_rnd_buffer` is not set, then it takes the value of `record_buffer`.

- Fixed optimizing bug in `ORDER BY` where some `ORDER BY` parts where wrongly removed.

- Fixed overflow bug with `ALTER TABLE` and `MERGE` tables.

- Added prototypes for `my_thread_init()` and `my_thread_end()` to `mysql_com.h`

- Added `--safe-user-create` option to `mysqld`.

- Fixed bug in `SELECT DISTINCT ... HAVING` that caused error message `Can't find record in #...`

### C.4.20. Changements de la version 3.23.40

- Fixed problem with `--low-priority-updates` and `INSERT` statements.

- Fixed bug in slave thread when under some rare circumstances it could get 22 bytes ahead on the offset in the master.

- Added `slave_net_timeout` for replication.

- Fixed problem with `UPDATE` and `BDB` tables.

- Fixed hard bug in `BDB` tables when using key parts.

- Fixed problem when using `GRANT FILE ON database.* ...`; previously we added the `DROP` privilege for the database.

- Fixed `DELETE FROM tbl_name ... LIMIT 0` and `UPDATE FROM tbl_name ... LIMIT 0`, which acted as though the `LIMIT` clause was not present (they deleted or updated all selected rows).

- `CHECK TABLE` now checks if an `AUTO_INCREMENT` column contains the value 0.

- Sending a `SIGHUP` to `mysqld` will now only flush the logs, not reset the replication.

- Fixed parser to allow floats of type `1.0e1` (no sign after `e`).

- Option `--force` to `myisamchk` now also updates states.

- Added option `--warnings` to `mysqld`. Now `mysqld` prints the error `Aborted connection` only if this option is used.

- Fixed problem with `SHOW CREATE TABLE` when you didn't have a `PRIMARY KEY`.

- Properly fixed the rename of `innodb_unix_file_flush_method` variable to `innodb_flush_method`.

- Fixed bug when converting `BIGINT UNSIGNED` to `DOUBLE`. This caused a problem when doing comparisons with `BIGINT` values outside of the signed range.

- Fixed bug in `BDB` tables when querying empty tables.

- Fixed a bug when using `COUNT(DISTINCT)` with `LEFT JOIN` and there weren't any matching rows.

- Removed all documentation referring to the `GEMINI` table type. `GEMINI` is not released under an `Open Source` license.

### C.4.21. Changements de la version 3.23.39 (12 juin 2001)

- The `AUTO_INCREMENT` sequence wasn't reset when dropping and adding an `AUTO_INCREMENT` column.

- `CREATE ... SELECT` now creates non-unique indexes delayed.

- Fixed problem where `LOCK TABLES tbl_name READ` followed by `FLUSH TABLES` put an exclusive lock on the table.

- `REAL @variable` values were represented with only 2 digits when converted to strings.

- Fixed problem that client ``hung'' when `LOAD TABLE FROM MASTER` failed.

- `myisamchk --fast --force` will no longer repair tables that only had the open count wrong.

- Added functions to handle symbolic links to make life easier in 4.0.

- We are now using the `-lcma` thread library on HP-UX 10.20 so that MySQL will be more stable on HP-UX.

- Fixed problem with `IF()` and number of decimals in the result.

- Fixed date-part extraction functions to work with dates where day and/or month is 0.

- Extended argument length in option files from 256 to 512 chars.

- Fixed problem with shutdown when `INSERT DELAYED` was waiting for a `LOCK TABLE`.

- Fixed core dump bug in `InnoDB` when tablespace was full.

- Fixed problem with `MERGE` tables and big tables (> 4G) when using `ORDER BY`.

### C.4.22. Changements de la version 3.23.38 (09 mai 2001)

- Fixed a bug when `SELECT` from `MERGE` table sometimes results in incorrectly ordered rows.

- Fixed a bug in `REPLACE()` when using the `ujis` character set.

- Applied Sleepycat `BDB` patches 3.2.9.1 and 3.2.9.2.

- Added `--skip-stack-trace` option to `mysqld`.

- `CREATE TEMPORARY` now works with `InnoDB` tables.

- `InnoDB` now promotes sub keys to whole keys.

- Added option `CONCURRENT` to `LOAD DATA`.

- Better error message when slave `max_allowed_packet` is too low to read a very long log event from the master.

- Fixed bug when too many rows where removed when using `SELECT DISTINCT ... HAVING`.

- `SHOW CREATE TABLE` now returns `TEMPORARY` for temporary tables.

- Added `Rows_examined` to slow query log.

- Fixed problems with function returning empty string when used together with a group function and a `WHERE` that didn't match any rows.

- New program `mysqlcheck`.

- Added database name to output for administrative commands like `CHECK`, `REPAIR`, `OPTIMIZE`.

- Lots of portability fixes for `InnoDB`.

- Changed optimizer so that queries like `SELECT * FROM tbl_name,tbl_name2 ... ORDER BY key_part1 LIMIT row_count` will use index on `key_part1` instead of `filesort`.

- Fixed bug when doing `LOCK TABLE to_table WRITE,...; INSERT INTO to_table... SELECT ...` when `to_table` was empty.

- Fixed bug with `LOCK TABLE` and `BDB` tables.

### C.4.23. Changements de la version 3.23.37 (17 avril 2001)

- Fixed a bug when using `MATCH()` in `HAVING` clause.

- Fixed a bug when using `HEAP` tables with `LIKE`.

- Added `--mysql-version` option to `safe_mysqld`

- Changed `INNOBASE` to `InnoDB` (because the `INNOBASE` name was already used). All `configure` options and `mysqld` start options now use `innodb` instead of `innobase`. This means that before upgrading to this version, you have to change any configuration files where you have used `innobase` options!

- Fixed bug when using indexes on `CHAR(255) NULL` columns.

- Slave thread will now be started even if `master-host` is not set, as long as `server-id` is set and valid `master.info` is present.

- Partial updates (terminated with kill) are now logged with a special error code to the binary log. Slave will refuse to execute them if the error code indicates the update was terminated abnormally, and will have to be recovered with `SET SQL_SLAVE_SKIP_COUNTER=1; SLAVE START` after a manual sanity check/correction of data integrity.

- Fixed bug that erroneously logged a drop of internal temporary table on thread termination to the binary log --- this bug affected replication.

- Fixed a bug in `REGEXP` on 64-bit machines.

- `UPDATE` and `DELETE` with `WHERE unique_key_part IS NULL` didn't update/delete all rows.

- Disabled `INSERT DELAYED` for tables that support transactions.

- Fixed bug when using date functions on `TEXT`/`BLOB` column with wrong date format.

- UDFs now also work on Windows. (Patch by Ralph Mason.)

- Fixed bug in `ALTER TABLE` and `LOAD DATA INFILE` that disabled key-sorting. These commands should now be faster in most cases.

- Fixed performance bug where reopened tables (tables that had been waiting for `FLUSH` or `REPAIR`) would not use indexes for the next query.

- Fixed problem with `ALTER TABLE` to `InnoDB` tables on FreeBSD.

- Added `mysqld` variables `myisam_max_sort_file_size` and `myisam_max_extra_sort_file_size`.

- Initialize signals early to avoid problem with signals in `InnoDB`.

- Applied patch for the `tis620` character set to make comparisons case-independent and to fix a bug in `LIKE` for this character set. Note: All tables that uses the `tis620` character set must be fixed with `myisamchk -r` or `REPAIR TABLE` !

- Added `--skip-safemalloc` option to `mysqld`.

### C.4.24. Changements de la version 3.23.36 (27 mars 2001)

- Fixed a bug that allowed use of database names containing a ‘`.`’ character. This fixes a serious security issue when `mysqld` is run as root.

- Fixed bug when thread creation failed (could happen when doing a lot of connections in a short time).

- Fixed some problems with `FLUSH TABLES` and `TEMPORARY` tables. (Problem with freeing the key cache and error `Can't reopen table...`.)

- Fixed a problem in `InnoDB` with other character sets than `latin1` and another problem when using many columns.

- Fixed bug that caused a core dump when using a very complex query involving `DISTINCT` and summary functions.

- Added `SET TRANSACTION ISOLATION LEVEL ...`

- Added `SELECT ... FOR UPDATE`.

- Fixed bug where the number of affected rows was not returned when MySQL was compiled without transaction support.

- Fixed a bug in `UPDATE` where keys weren't always used to find the rows to be updated.

- Fixed a bug in `CONCAT_WS()` where it returned incorrect results.

- Changed `CREATE ... SELECT` and `INSERT ... SELECT` to not allow concurrent inserts as this could make the binary log hard to repeat. (Concurrent inserts are enabled if you are not using the binary or update log.)

- Changed some macros to be able to use fast mutex with `glibc` 2.2.

### C.4.25. Changements de la version 3.23.35 (15 mars 2001)

- Fixed newly introduced bug in `ORDER BY`.

- Fixed wrong define `CLIENT_TRANSACTIONS`.

- Fixed bug in `SHOW VARIABLES` when using `INNOBASE` tables.

- Setting and using user variables in `SELECT DISTINCT` didn't work.

- Tuned `SHOW ANALYZE` for small tables.

- Fixed handling of arguments in the benchmark script `run-all-tests`.

### C.4.26. Changements de la version 3.23.34a

- Added extra files to the distribution to allow `INNOBASE` support to be compiled.

### C.4.27. Changements de la version 3.23.34 (10 mars 2001)

- Added the `INNOBASE` storage engine and the `BDB` storage engine to the MySQL source distribution.

- Updated the documentation about `GEMINI` tables.

- Fixed a bug in `INSERT DELAYED` that caused threads to hang when inserting `NULL` into an `AUTO_INCREMENT` column.

- Fixed a bug in `CHECK TABLE` / `REPAIR TABLE` that could cause a thread to hang.

- `REPLACE` will not replace a row that conflicts with an `AUTO_INCREMENT` generated key.

- `mysqld` now only sets `CLIENT_TRANSACTIONS` in `mysql->server_capabilities` if the server supports a transaction-safe storage engine.

- Fixed `LOAD DATA INFILE` to allow numeric values to be read into `ENUM` and `SET` columns.

- Improved error diagnostic for slave thread exit.

- Fixed bug in `ALTER TABLE ... ORDER BY`.

- Added `max_user_connections` variable to `mysqld`.

- Limit query length for replication by `max_allowed_packet`, not the arbitrary limit of 4 MB.

- Allow space around `=` in argument to `--set-variable`.

- Fixed problem in automatic repair that could leave some threads in state `Waiting for table`.

- `SHOW CREATE TABLE` now displays the `UNION=()` for `MERGE` tables.

- `ALTER TABLE` now remembers the old `UNION=()` definition.

- Fixed bug when replicating timestamps.

- Fixed bug in bidirectional replication.

- Fixed bug in the `BDB` storage engine that occurred when using an index on multi-part key where a key part may be `NULL`.

- Fixed `MAX()` optimization on sub-key for `BDB` tables.

- Fixed problem where garbage results were returned when using `BDB` tables and `BLOB` or `TEXT` fields when joining many tables.

- Fixed a problem with `BDB` tables and `TEXT` columns.

- Fixed bug when using a `BLOB` key where a const row wasn't found.

- Fixed that `mysqlbinlog` writes the timestamp value for each query. This ensures that one gets same values for date functions like `NOW()` when using `mysqlbinlog` to pipe the queries to another server.

- Allow `--skip-gemini`, `--skip-bdb`, and `--skip-innodb` options to be specified when invoking `mysqld`, even if these storage engines are not compiled in to `mysqld`.

- One can now do `GROUP BY ... DESC`.

- Fixed a deadlock in the `SET` code, when one ran `SET @foo=bar`, where `bar` is a column reference, an error was not properly generated.

### C.4.28. Changements de la version 3.23.33 (09 février 2001)

- Fixed DNS lookups not to use the same mutex as the hostname cache. This will enable known hosts to be quickly resolved even if a DNS lookup takes a long time.

- Added `--character-sets-dir` option to `myisampack`.

- Removed warnings when running `REPAIR TABLE ... EXTENDED`.

- Fixed a bug that caused a core dump when using `GROUP BY` on an alias, where the alias was the same as an existing column name.

- Added `SEQUENCE()` as an example `UDF` function.

- Changed `mysql_install_db` to use `BINARY` for `CHAR` columns in the privilege tables.

- Changed `TRUNCATE tbl_name` to `TRUNCATE TABLE tbl_name` to use the same syntax as Oracle. Until 4.0 we will also allow `TRUNCATE tbl_name` to not crash old code.

- Fixed ``no found rows'' bug in `MyISAM` tables when a `BLOB` was first part of a multi-part key.

- Fixed bug where `CASE` didn't work with `GROUP BY`.

- Added `--sort-recover` option to `myisamchk`.

- `myisamchk -S` and `OPTIMIZE TABLE` now work on Windows.

- Fixed bug when using `DISTINCT` on results from functions that referred to a group function, like:

      SELECT a, DISTINCT SEC_TO_TIME(SUM(a))
      FROM tbl_name GROUP BY a, b;

- Fixed buffer overrun in `libmysqlclient` library. Fixed bug in handling `STOP` event after `ROTATE` event in replication.

- Fixed another buffer overrun in `DROP DATABASE`.

- Added `Table_locks_immediate` and `Table_locks_waited` status variables.

- Fixed bug in replication that broke slave server start with existing `master.info`. This fixes a bug introduced in 3.23.32.

- Added `SET SQL_SLAVE_SKIP_COUNTER=n` command to recover from replication glitches without a full database copy.

- Added `max_binlog_size` variable; the binary log will be rotated automatically when the size crosses the limit.

- Added `Last_Error`, `Last_Errno`, and `Slave_skip_counter` variables to `SHOW SLAVE STATUS`.

- Fixed bug in `MASTER_POS_WAIT()` function.

- Execute core dump handler on `SIGILL`, and `SIGBUS` in addition to `SIGSEGV`.

- On x86 Linux, print the current query and thread (connection) id, if available, in the core dump handler.

- Fixed several timing bugs in the test suite.

- Extended `mysqltest` to take care of the timing issues in the test suite.

- `ALTER TABLE` can now be used to change the definition for a `MERGE` table.

- Fixed creation of `MERGE` tables on Windows.

- Portability fixes for OpenBSD and OS/2.

- Added `--temp-pool` option to `mysqld`. Using this option will cause most temporary files created to use a small set of names, rather than a unique name for each new file. This is to work around a problem in the Linux kernel dealing with creating a bunch of new files with different names. With the old behavior, Linux seems to "leak" memory, as it's being allocated to the directory entry cache instead of the disk cache.

### C.4.29. Changements de la version 3.23.32 (22 Jan 2001: Production)

- Changed code to get around compiler bug in Compaq C++ on OSF/1, that broke `BACKUP`, `RESTORE`, `CHECK`, `REPAIR`, and `ANALYZE TABLE`.

- Added option `FULL` to `SHOW COLUMNS`. Now we show the privilege list for the columns only if this option is given.

- Fixed bug in `SHOW LOGS` when there weren't any `BDB` logs.

- Fixed a timing problem in replication that could delay sending an update to the client until a new update was done.

- Don't convert field names when using `mysql_list_fields()`. This is to keep this code compatible with `SHOW FIELDS`.

- `MERGE` tables didn't work on Windows.

- Fixed problem with `SET PASSWORD=...` on Windows.

- Added missing `my_config.h` to RPM distribution.

- `TRIM("foo" from "foo")` didn't return an empty string.

- Added `--with-version-suffix` option to `configure`.

- Fixed core dump when client aborted connection without `mysql_close()`.

- Fixed a bug in `RESTORE TABLE` when trying to restore from a non-existent directory.

- Fixed a bug which caused a core dump on the slave when replicating `SET PASSWORD`.

- Added `MASTER_POS_WAIT()`.

### C.4.30. Changements de la version 3.23.31 (17 janvier 2001)

- The test suite now tests all reachable `BDB` interface code. During testing we found and fixed many errors in the interface code.

- Using `HAVING` on an empty table could produce one result row when it shouldn't.

- Fixed the MySQL RPM so it no longer depends on Perl5.

- Fixed some problems with `HEAP` tables on Windows.

- `SHOW TABLE STATUS` didn't show correct average row length for tables larger than 4G.

- `CHECK TABLE ... EXTENDED` didn't check row links for fixed size tables.

- Added option `MEDIUM` to `CHECK TABLE`.

- Fixed problem when using `DECIMAL()` keys on negative numbers.

- `HOUR()` (and some other `TIME` functions) on a `CHAR` column always returned `NULL`.

- Fixed security bug in something (please upgrade if you are using an earlier MySQL 3.23 version).

- Fixed buffer overflow bug when writing a certain error message.

- Added usage of `setrlimit()` on Linux to get `-O --open-files-limit=#` to work on Linux.

- Added `bdb_version` variable to `mysqld`.

- Fixed bug when using expression of type:

      SELECT ... FROM t1 LEFT JOIN t2 ON (t1.a=t2.a) WHERE t1.a=t2.a

  In this case the test in the `WHERE` clause was wrongly optimized away.

- Fixed bug in `MyISAM` when deleting keys with possible `NULL` values, but the first key-column was not a prefix-compressed text column.

- Fixed `mysql.server` to read the `[mysql.server]` option file group rather than the `[mysql_server]` group.

- Fixed `safe_mysqld` and `mysql.server` to also read the `server` option section.

- Added `Threads_created` status variable to `mysqld`.

### C.4.31. Changements de la version 3.23.30 (04 janvier 2001)

- Added `SHOW OPEN TABLES` command.

- Fixed that `myisamdump` works against old `mysqld` servers.

- Fixed `myisamchk -k#` so that it works again.

- Fixed a problem with replication when the binary log file went over 2G on 32-bit systems.

- `LOCK TABLES` will now automatically start a new transaction.

- Changed `BDB` tables to not use internal subtransactions and reuse open files to get more speed.

- Added `--mysqld=#` option to `safe_mysqld`.

- Allow hex constants in the `--fields-*-by` and `--lines-terminated-by` options to `mysqldump` and `mysqlimport`. By Paul DuBois.

- Added `--safe-show-database` option to `mysqld`.

- Added `have_bdb`, `have_gemini`, `have_innobase`, `have_raid` and `have_openssl` to `SHOW VARIABLES` to make it easy to test for supported extensions.

- Added `--open-files-limit` option to `mysqld`.

- Changed `--open-files` option to `--open-files-limit` in `safe_mysqld`.

- Fixed a bug where some rows were not found with `HEAP` tables that had many keys.

- Fixed that `--bdb-no-sync` works.

- Changed `--bdb-recover` to `--bdb-no-recover` as recover should be on by default.

- Changed the default number of `BDB` locks to 10000.

- Fixed a bug from 3.23.29 when allocating the shared structure needed for `BDB` tables.

- Changed `mysqld_multi.sh` to use configure variables. Patch by Christopher McCrory.

- Added fixing of include files for Solaris 2.8.

- Fixed bug with `--skip-networking` on Debian Linux.

- Fixed problem that some temporary files where reported as having the name `UNOPENED` in error messages.

- Fixed bug when running two simultaneous `SHOW LOGS` queries.

### C.4.32. Changements de la version 3.23.29 (16 décembre 2000)

- Configure updates for Tru64, large file support, and better TCP wrapper support. By Albert Chin-A-Young.

- Fixed bug in `<=>` operator.

- Fixed bug in `REPLACE` with `BDB` tables.

- `LPAD()` and `RPAD()` will shorten the result string if it's longer than the length argument.

- Added `SHOW LOGS` command.

- Remove unused `BDB` logs on shutdown.

- When creating a table, put `PRIMARY` keys first, followed by `UNIQUE` keys.

- Fixed a bug in `UPDATE` involving multi-part keys where one specified all key parts both in the update and the `WHERE` part. In this case MySQL could try to update a record that didn't match the whole `WHERE` part.

- Changed drop table to first drop the tables and then the `.frm` file.

- Fixed a bug in the hostname cache which caused `mysqld` to report the hostname as `''` in some error messages.

- Fixed a bug with `HEAP` type tables; the variable `max_heap_table_size` wasn't used. Now either `MAX_ROWS` or `max_heap_table_size` can be used to limit the size of a `HEAP` type table.

- Changed the default server-id to 1 for masters and 2 for slaves to make it easier to use the binary log.

- Renamed `bdb_lock_max` variable to `bdb_max_lock`.

- Added support for `AUTO_INCREMENT` on sub-fields for `BDB` tables.

- Added `ANALYZE` of `BDB` tables.

- In `BDB` tables, we now store the number of rows; this helps to optimize queries when we need an approximation of the number of rows.

- If we get an error in a multi-row statement, we now only roll back the last statement, not the entire transaction.

- If you do a `ROLLBACK` when you have updated a non-transactional table you will get an error as a warning.

- Added `--bdb-shared-data` option to `mysqld`.

- Added `Slave_open_temp_tables` status variable to `mysqld`

- Added `binlog_cache_size` and `max_binlog_cache_size` variables to `mysqld`.

- `DROP TABLE`, `RENAME TABLE`, `CREATE INDEX` and `DROP INDEX` are now transaction endpoints.

- If you do a `DROP DATABASE` on a symbolically linked database, both the link and the original database is deleted.

- Fixed `DROP DATABASE` to work on OS/2.

- Fixed bug when doing a `SELECT DISTINCT ... table1 LEFT JOIN table2 ...` when `table2` was empty.

- Added `--abort-slave-event-count` and `--disconnect-slave-event-count` options to `mysqld` for debugging and testing of replication.

- Fixed replication of temporary tables. Handles everything except slave server restart.

- `SHOW KEYS` now shows whether key is `FULLTEXT`.

- New script `mysqld_multi`. See Section 5.1.5, « `mysqld_multi`, un programme pour gérer plusieurs serveurs MySQL ».

- Added new script, `mysql-multi.server.sh`. Thanks to Tim Bunce `<Tim.Bunce@ig.co.uk>` for modifying `mysql.server` to easily handle hosts running many `mysqld` processes.

- `safe_mysqld`, `mysql.server`, and `mysql_install_db` have been modified to use `mysql_print_defaults` instead of various hacks to read the `my.cnf` files. In addition, the handling of various paths has been made more consistent with how `mysqld` handles them by default.

- Automatically remove Berkeley DB transaction logs that no longer are in use.

- Fixed bug with several `FULLTEXT` indexes in one table.

- Added a warning if number of rows changes on `REPAIR`/`OPTIMIZE`.

- Applied patches for OS/2 by `Yuri Dario`.

- `FLUSH TABLES tbl_name` didn't always flush the index tree to disk properly.

- `--bootstrap` is now run in a separate thread. This fixes a problem that caused `mysql_install_db` to core dump on some Linux machines.

- Changed `mi_create()` to use less stack space.

- Fixed bug with optimizer trying to over-optimize `MATCH()` when used with `UNIQUE` key.

- Changed `crash-me` and the MySQL benchmarks to also work with FrontBase.

- Allow `RESTRICT` and `CASCADE` after `DROP TABLE` to make porting easier.

- Reset status variable which could cause problem if one used `--slow-log`.

- Added `connect_timeout` variable to `mysql` and `mysqladmin`.

- Added `connect-timeout` as an alias for `timeout` for option files read by `mysql_options()`.

### C.4.33. Changements de la version 3.23.28 (22 Nov 2000: Gamma)

- Added new options `--pager[=...]`, `--no-pager`, `--tee=...` and `--no-tee` to the `mysql` client. The new corresponding interactive commands are `pager`, `nopager`, `tee` and `notee`. See Section 8.3, « `mysql`, l'outil en ligne de commande », `mysql --help` and the interactive help for more information.

- Fixed crash when automatic repair of `MyISAM` table failed.

- Fixed a major performance bug in the table locking code when one constantly had a lot of `SELECT`, `UPDATE` and `INSERT` statements running. The symptom was that the `UPDATE` and `INSERT` queries were locked for a long time while new `SELECT` statements were executed before the updates.

- When reading `options_files` with `mysql_options()` the `return-found-rows` option was ignored.

- One can now specify `interactive-timeout` in the option file that is read by `mysql_options()`. This makes it possible to force programs that run for a long time (like `mysqlhotcopy`) to use the `interactive_timeout` time instead of the `wait_timeout` time.

- Added to the slow query log the time and the user name for each logged query. If you are using `--log-long-format` then also queries that do not use an index are logged, even if the query takes less than `long_query_time` seconds.

- Fixed a problem in `LEFT JOIN` which caused all columns in a reference table to be `NULL`.

- Fixed a problem when using `NATURAL JOIN` without keys.

- Fixed a bug when using a multi-part keys where the first part was of type `TEXT` or `BLOB`.

- `DROP` of temporary tables wasn't stored in the update/binary log.

- Fixed a bug where `SELECT DISTINCT * ... LIMIT row_count` only returned one row.

- Fixed a bug in the assembler code in `strstr()` for SPARC and cleaned up the `global.h` header file to avoid a problem with bad aliasing with the compiler submitted with Red Hat 7.0. (Reported by Trond Eivind Glomsrød)

- The `--skip-networking` option now works properly on NT.

- Fixed a long outstanding bug in the `ISAM` tables when a row with a length of more than 65K was shortened by a single byte.

- Fixed a bug in `MyISAM` when running multiple updating processes on the same table.

- Allow one to use `FLUSH TABLE tbl_name`.

- Added `--replicate-ignore-table`, `--replicate-do-table`, `--replicate-wild-ignore-table`, and `--replicate-wild-do-table` options to `mysqld`.

- Changed all log files to use our own `IO_CACHE` mechanism instead of `FILE` to avoid OS problems when there are many files open.

- Added `--open-files` and `--timezone` options to `safe_mysqld`.

- Fixed a fatal bug in `CREATE TEMPORARY TABLE ... SELECT ...`.

- Fixed a problem with `CREATE TABLE ... SELECT NULL`.

- Added variables `large_file_support`,`net_read_timeout`, `net_write_timeout` and `query_buffer_size` to `SHOW VARIABLES`.

- Added status variables `created_tmp_files` and `sort_merge_passes` to `SHOW STATUS`.

- Fixed a bug where we didn't allow an index name after the `FOREIGN KEY` definition.

- Added `TRUNCATE table_name` as a synonym for `DELETE FROM table_name`.

- Fixed a bug in a `BDB` key compare function when comparing part keys.

- Added `bdb_lock_max` variable to `mysqld`.

- Added more tests to the benchmark suite.

- Fixed an overflow bug in the client code when using overly long database names.

- `mysql_connect()` now aborts on Linux if the server doesn't answer in `timeout` seconds.

- `SLAVE START` did not work if you started with `--skip-slave-start` and had not explicitly run `CHANGE MASTER TO`.

- Fixed the output of `SHOW MASTER STATUS` to be consistent with `SHOW SLAVE STATUS`. (It now has no directory in the log name.)

- Added `PURGE MASTER LOGS TO`.

- Added `SHOW MASTER LOGS`.

- Added `--safemalloc-mem-limit` option to `mysqld` to simulate memory shortage when compiled with the `--with-debug=full` option.

- Fixed several core dumps in out-of-memory conditions.

- `SHOW SLAVE STATUS` was using an uninitialized mutex if the slave had not been started yet.

- Fixed bug in `ELT()` and `MAKE_SET()` when the query used a temporary table.

- `CHANGE MASTER TO` without specifying `MASTER_LOG_POS` would set it to 0 instead of 4 and hit the magic number in the master binlog.

- `ALTER TABLE ... ORDER BY ...` syntax added. This will create the new table with the rows in a specific order.

### C.4.34. Changements de la version 3.23.27 (24 octobre 2000)

- Fixed a bug where the automatic repair of `MyISAM` tables sometimes failed when the datafile was corrupt.

- Fixed a bug in `SHOW CREATE` when using `AUTO_INCREMENT` columns.

- Changed `BDB` tables to use new compare function in Berkeley DB 3.2.3.

- You can now use Unix sockets with MIT-pthreads.

- Added the `latin5` (turkish) character set.

- Small portability fixes.

### C.4.35. Changements de la version 3.23.26 (18 octobre 2000)

- Renamed `FLUSH MASTER` and `FLUSH SLAVE` to `RESET MASTER` and `RESET SLAVE`.

- Fixed `<>` to work properly with `NULL`.

- Fixed a problem with `SUBSTRING_INDEX()` and `REPLACE()`. (Patch by Alexander Igonitchev)

- Fix `CREATE TEMPORARY TABLE IF NOT EXISTS` not to produce an error if the table exists.

- If you don't create a `PRIMARY KEY` in a `BDB` table, a hidden `PRIMARY KEY` will be created.

- Added read-only-key optimization to `BDB` tables.

- `LEFT JOIN` in some cases preferred a full table scan when there was no `WHERE` clause.

- When using `--log-slow-queries`, don't count the time waiting for a lock.

- Fixed bug in lock code on Windows which could cause the key cache to report that the key file was crashed even if it was okay.

- Automatic repair of `MyISAM` tables if you start `mysqld` with `--myisam-recover`.

- Removed the `TYPE=` keyword from `CHECK` and `REPAIR`. Allow `CHECK` options to be combined. (You can still use `TYPE=`, but this usage is deprecated.)

- Fixed mutex bug in the binary replication log --- long update queries could be read only in part by the slave if it did it at the wrong time, which was not fatal, but resulted in a performance-degrading reconnect and a scary message in the error log.

- Changed the format of the binary log --- added magic number, server version, binlog version. Added the server ID and query error code for each query event.

- Replication thread from the slave now will kill all the stale threads from the same server.

- Long replication user names were not being handled properly.

- Added `--replicate-rewrite-db` option to `mysqld`.

- Added `--skip-slave-start` option to `mysqld`.

- Updates that generated an error code (such as `INSERT INTO foo(some_key) values (1),(1)`) erroneously terminated the slave thread.

- Added optimization of queries where `DISTINCT` is only used on columns from some of the tables.

- Allow floating-point numbers where there is no sign after the exponent (like `1e1`).

- `SHOW GRANTS` didn't always show all column grants.

- Added `--default-extra-file=#` option to all MySQL clients.

- Columns referenced in `INSERT` statements now are initialized properly.

- `UPDATE` didn't always work when used with a range on a timestamp that was part of the key that was used to find rows.

- Fixed a bug in `FULLTEXT` index when inserting a `NULL` column.

- Changed to use `mkstemp()` instead of `tempnam()`. Based on a patch from John Jones.

### C.4.36. Changements de la version 3.23.25 (29 septembre 2000)

- Fixed that `databasename` works as second argument to `mysqlhotcopy`.

- The values for the `UMASK` and `UMASK_DIR` environment variables now can be specified in octal by beginning the value with a zero.

- Added `RIGHT JOIN`. This makes `RIGHT` a reserved word.

- Added `@@IDENTITY` as a synonym for `LAST_INSERT_ID()`. (This is for MSSQL compatibility.)

- Fixed a bug in `myisamchk` and `REPAIR` when using `FULLTEXT` index.

- `LOAD DATA INFILE` now works with FIFOs. (Patch by Toni L. Harbaugh-Blackford.)

- `FLUSH LOGS` broke replication if you specified a log name with an explicit extension as the value of the `log-bin` option.

- Fixed a bug in `MyISAM` with packed multi-part keys.

- Fixed crash when using `CHECK TABLE` on Windows.

- Fixed a bug where `FULLTEXT` index always used the `koi8_ukr` character set.

- Fixed privilege checking for `CHECK TABLE`.

- The `MyISAM` repair/reindex code didn't use the `--tmpdir` option for its temporary files.

- Added `BACKUP TABLE` and `RESTORE TABLE`.

- Fixed core dump on `CHANGE MASTER TO` when the slave did not have the master to start with.

- Fixed incorrect `Time` in the processlist for `Connect` of the slave thread.

- The slave now logs when it connects to the master.

- Fixed a core dump bug when doing `FLUSH MASTER` if you didn't specify a filename argument to `--log-bin`.

- Added missing `ha_berkeley.x` files to the MySQL Windows distribution.

- Fixed some mutex bugs in the log code that could cause thread blocks if new log files couldn't be created.

- Added lock time and number of selected processed rows to slow query log.

- Added `--memlock` option to `mysqld` to lock `mysqld` in memory on systems with the `mlockall()` call (as in Solaris).

- `HEAP` tables didn't use keys properly. (Bug from 3.23.23.)

- Added better support for `MERGE` tables (keys, mapping, creation, documentation...). See Section 14.2, « Tables assemblées `MERGE` ».

- Fixed bug in `mysqldump` from 3.23 which caused some `CHAR` columns not to be quoted.

- Merged `analyze`, `check`, `optimize` and repair code.

- `OPTIMIZE TABLE` is now mapped to `REPAIR` with statistics and sorting of the index tree. This means that for the moment it only works on `MyISAM` tables.

- Added a pre-alloced block to root_malloc to get fewer mallocs.

- Added a lot of new statistics variables.

- Fixed `ORDER BY` bug with `BDB` tables.

- Removed warning that `mysqld` couldn't remove the `.pid` file under Windows.

- Changed `--log-isam` to log `MyISAM` tables instead of isam tables.

- Fixed `CHECK TABLE` to work on Windows.

- Added file mutexes to make `pwrite()` safe on Windows.

### C.4.37. Changements de la version 3.23.24 (08 septembre 2000)

- Added `created_tmp_disk_tables` variable to `mysqld`.

- To make it possible to reliably dump and restore tables with `TIMESTAMP(X)` columns, MySQL now reports columns with `X` other than 14 or 8 to be strings.

- Changed sort order for `latin1` as it was before MySQL Version 3.23.23. Any table that was created or modified with 3.23.22 must be repaired if it has `CHAR` columns that may contain characters with ASCII values greater than 128!

- Fixed small memory leak introduced from 3.23.22 when creating a temporary table.

- Fixed problem with `BDB` tables and reading on a unique (not primary) key.

- Restored the `win1251` character set (it's now only marked deprecated).

### C.4.38. Changements de la version 3.23.23 (01 septembre 2000)

- Changed sort order for 'German'; all tables created with 'German' sortorder must be repaired with `REPAIR TABLE` or `myisamchk` before use!

- Added `--core-file` option to `mysqld` to get a core file on Linux if `mysqld` dies on the `SIGSEGV` signal.

- MySQL client `mysql` now starts with option `--no-named-commands` (`-g`) by default. This option can be disabled with `--enable-named-commands` (`-G`). This may cause incompatibility problems in some cases, for example, in SQL scripts that use named commands without a semicolon, etc.! Long format commands still work from the first line.

- Fixed a problem when using many pending `DROP TABLE` statements at the same time.

- Optimizer didn't use keys properly when using `LEFT JOIN` on an empty table.

- Added shorter help text when invoking `mysqld` with incorrect options.

- Fixed non-fatal `free()` bug in `mysqlimport`.

- Fixed bug in `MyISAM` index handling of `DECIMAL`/`NUMERIC` keys.

- Fixed a bug in concurrent insert in `MyISAM` tables. In some contexts, usage of `MIN(key_part)` or `MAX(key_part)` returned an empty set.

- Updated `mysqlhotcopy` to use the new `FLUSH TABLES table_list` syntax. Only tables which are being backed up are flushed now.

- Changed behavior of `--enable-thread-safe-client` so that both non-threaded (`-lmysqlclient`) and threaded (`-lmysqlclient_r`) libraries are built. Users who linked against a threaded `-lmysqlclient` will need to link against `-lmysqlclient_r` now.

- Added atomic `RENAME TABLE` command.

- Don't count `NULL` values in `COUNT(DISTINCT ...)`.

- Changed `ALTER TABLE`, `LOAD DATA INFILE` on empty tables and `INSERT ... SELECT ...` on empty tables to create non-unique indexes in a separate batch with sorting. This will make the above calls much faster when you have many indexes.

- `ALTER TABLE` now logs the first used insert_id correctly.

- Fixed crash when adding a default value to a `BLOB` column.

- Fixed a bug with `DATE_ADD/DATE_SUB` where it returned a datetime instead of a date.

- Fixed a problem with the thread cache which made some threads show up as `***DEAD***` in `SHOW PROCESSLIST`.

- Fixed a lock in our thr_rwlock code, which could make selects that run at the same time as concurrent inserts crash. This only affects systems that don't have the `pthread_rwlock_rdlock` code.

- When deleting rows with a non-unique key in a `HEAP` table, all rows weren't always deleted.

- Fixed bug in range optimizer for `HEAP` tables for searches on a part index.

- Fixed `SELECT` on part keys to work with `BDB` tables.

- Fixed `INSERT INTO bdb_table ... SELECT` to work with `BDB` tables.

- `CHECK TABLE` now updates key statistics for the table.

- `ANALYZE TABLE` will now only update tables that have been changed since the last `ANALYZE`. Note that this is a new feature and tables will not be marked to be analysed until they are updated in any way with 3.23.23 or newer. For older tables, you have to do `CHECK TABLE` to update the key distribution.

- Fixed some minor privilege problems with `CHECK`, `ANALYZE`, `REPAIR` and `SHOW CREATE` commands.

- Added `CHANGE MASTER TO` statement.

- Added `FAST`, `QUICK` `EXTENDED` check types to `CHECK TABLES`.

- Changed `myisamchk` so that `--fast` and `--check-only-changed` are also honored with `--sort-index` and `--analyze`.

- Fixed fatal bug in `LOAD TABLE FROM MASTER` that did not lock the table during index re-build.

- `LOAD DATA INFILE` broke replication if the database was excluded from replication.

- More variables in `SHOW SLAVE STATUS` and `SHOW MASTER STATUS`.

- `SLAVE STOP` now will not return until the slave thread actually exits.

- Full-text search via the `MATCH()` function and `FULLTEXT` index type (for `MyISAM` files). This makes `FULLTEXT` a reserved word.

### C.4.39. Changements de la version 3.23.22 (31 juillet 2000)

- Fixed that `lex_hash.h` is created properly for each MySQL distribution.

- Fixed that `MASTER` and `COLLECTION` are not reserved words.

- The log generated by `--slow-query-log` didn't contain the whole queries.

- Fixed that open transactions in `BDB` tables are rolled back if the connection is closed unexpectedly.

- Added workaround for a bug in `gcc` 2.96 (intel) and `gcc` 2.9 (IA-64) in `gen_lex_hash.c`.

- Fixed memory leak in the client library when using `host=` in the `my.cnf` file.

- Optimized functions that manipulate the hours/minutes/seconds.

- Fixed bug when comparing the result of `DATE_ADD()`/`DATE_SUB()` against a number.

- Changed the meaning of `-F, --fast` for `myisamchk`. Added `-C, --check-only-changed` option to `myisamchk`.

- Added `ANALYZE tbl_name` to update key statistics for tables.

- Changed binary items `0x...` to be regarded as integers by default.

- Fix for SCO and `SHOW PROCESSLIST`.

- Added `auto-rehash` on reconnect for the `mysql` client.

- Fixed a newly introduced bug in `MyISAM`, where the index file couldn't get bigger than 64M.

- Added `SHOW MASTER STATUS` and `SHOW SLAVE STATUS`.

### C.4.40. Changements de la version 3.23.21

- Added `mysql_character_set_name()` function to the MySQL C API.

- Made the update log ASCII 0 safe.

- Added the `mysql_config` script.

- Fixed problem when using `<` or `>` with a char column that was only partly indexed.

- One would get a core dump if the log file was not readable by the MySQL user.

- Changed `mysqladmin` to use `CREATE DATABASE` and `DROP DATABASE` statements instead of the old deprecated API calls.

- Fixed `chown` warning in `safe_mysqld`.

- Fixed a bug in `ORDER BY` that was introduced in 3.23.19.

- Only optimize the `DELETE FROM tbl_name` to do a drop+create of the table if we are in `AUTOCOMMIT` mode (needed for `BDB` tables).

- Added extra checks to avoid index corruption when the `ISAM`/`MyISAM` index files get full during an `INSERT`/`UPDATE`.

- `myisamchk` didn't correctly update row checksum when used with `-ro` (this only gave a warning in subsequent runs).

- Fixed bug in `REPAIR TABLE` so that it works with tables without indexes.

- Fixed buffer overrun in `DROP DATABASE`.

- `LOAD TABLE FROM MASTER` is sufficiently bug-free to announce it as a feature.

- `MATCH` and `AGAINST` are now reserved words.

### C.4.41. Changements de la version 3.23.20

- Fixed bug in 3.23.19; `DELETE FROM tbl_name` removed the `.frm` file.

- Added `SHOW CREATE TABLE`.

### C.4.42. Changements de la version 3.23.19

- Changed copyright for all files to GPL for the server code and utilities and to LGPL for the client libraries. See http://www.fsf.org/licenses/.

- Fixed bug where all rows matching weren't updated on a `MyISAM` table when doing update based on key on a table with many keys and some key changed values.

- The Linux MySQL RPMs and binaries are now statically linked with a linuxthread version that has faster mutex handling when used with MySQL.

- `ORDER BY` can now use `REF` keys to find subsets of the rows that need to be sorted.

- Changed name of `print_defaults` program to `my_print_defaults` to avoid name confusion.

- Fixed `NULLIF()` to work as required by standard SQL.

- Added `net_read_timeout` and `net_write_timeout` as startup parameters to `mysqld`.

- Fixed bug that destroyed index when doing `myisamchk --sort-records` on a table with prefix compressed index.

- Added `pack_isam` and `myisampack` to the standard MySQL distribution.

- Added the syntax `BEGIN WORK` (the same as `BEGIN`).

- Fixed core dump bug when using `ORDER BY` on a `CONV()` expression.

- Added `LOAD TABLE FROM MASTER`.

- Added `FLUSH MASTER` and `FLUSH SLAVE`.

- Fixed big/little endian problem in the replication.

### C.4.43. Changements de la version 3.23.18

- Fixed a problem from 3.23.17 when choosing character set on the client side.

- Added `FLUSH TABLES WITH READ LOCK` to make a global lock suitable for making a copy of MySQL datafiles.

- `CREATE TABLE ... SELECT ... PROCEDURE` now works.

- Internal temporary tables will now use compressed index when using `GROUP BY` on `VARCHAR/CHAR` columns.

- Fixed a problem when locking the same table with both a `READ` and a `WRITE` lock.

- Fixed problem with `myisamchk` and `RAID` tables.

### C.4.44. Changements de la version 3.23.17

- Fixed a bug in `FIND_IN_SET()` when the first argument was `NULL`.

- Added table locks to Berkeley DB.

- Fixed a bug with `LEFT JOIN` and `ORDER BY` where the first table had only one matching row.

- Added 4 sample `my.cnf` example files in the `support-files` directory.

- Fixed `duplicated key` problem when doing big `GROUP BY` operations. (This bug was probably introduced in 3.23.15.)

- Changed syntax for `INNER JOIN` to match SQL-99.

- Added `NATURAL JOIN` syntax.

- A lot of fixes in the `BDB` interface.

- Added handling of `--no-defaults` and `--defaults-file` to `safe_mysqld.sh` and `mysql_install_db.sh`.

- Fixed bug in reading compressed tables with many threads.

- Fixed that `USE INDEX` works with `PRIMARY` keys.

- Added `BEGIN` statement to start a transaction in `AUTOCOMMIT` mode.

- Added support for symbolic links for Windows.

- Changed protocol to let client know if the server is in `AUTOCOMMIT` mode and if there is a pending transaction. If there is a pending transaction, the client library will give an error before reconnecting to the server to let the client know that the server did a rollback. The protocol is still backward-compatible with old clients.

- `KILL` now works on a thread that is locked on a 'write' to a dead client.

- Fixed memory leak in the replication slave thread.

- Added new `log-slave-updates` option to `mysqld`, to allow daisy-chaining the slaves.

- Fixed compile error on FreeBSD and other systems where `pthread_t` is not the same as `int`.

- Fixed master shutdown aborting the slave thread.

- Fixed a race condition in `INSERT DELAYED` code when doing `ALTER TABLE`.

- Added deadlock detection sanity checks to `INSERT DELAYED`.

### C.4.45. Changements de la version 3.23.16

- Added `SLAVE START` and `SLAVE STOP` statements.

- Added `TYPE=QUICK` option to `CHECK` and to `REPAIR`.

- Fixed bug in `REPAIR TABLE` when the table was in use by other threads.

- Added a thread cache to make it possible to debug MySQL with `gdb` when one does a lot of reconnects. This will also improve systems where you can't use persistent connections.

- Lots of fixes in the Berkeley DB interface.

- `UPDATE IGNORE` will not abort if an update results in a `DUPLICATE_KEY` error.

- Put `CREATE TEMPORARY TABLE` commands in the update log.

- Fixed bug in handling of masked IP numbers in the privilege tables.

- Fixed bug with `delay_key_write` tables and `CHECK TABLE`.

- Added `replicate-do-db` and `replicate-ignore-db` options to `mysqld`, to restrict which databases get replicated.

- Added `SQL_LOG_BIN` option.

### C.4.46. Changements de la version 3.23.15 (May 2000: Beta)

- To start `mysqld` as `root`, you must now use the `--user=root` option.

- Added interface to Berkeley DB. (This is not yet functional; play with it at your own risk!)

- Replication between master and slaves.

- Fixed bug that other threads could steal a lock when a thread had a lock on a table and did a `FLUSH TABLES` command.

- Added the `slow_launch_time` variable and the `Slow_launch_threads` status variable to `mysqld`. These can be examined with `mysqladmin variables` and `mysqladmin extended-status`.

- Added functions `INET_NTOA()` and `INET_ATON()`.

- The default type of `IF()` now depends on the second and third arguments and not only on the second argument.

- Fixed case when `myisamchk` could go into a loop when trying to repair a crashed table.

- Don't write `INSERT DELAYED` to update log if `SQL_LOG_UPDATE=0`.

- Fixed problem with `REPLACE` on `HEAP` tables.

- Added possible character sets and time zone to `SHOW VARIABLES` output.

- Fixed bug in locking code that could result in locking problems with concurrent inserts under high load.

- Fixed a problem with `DELETE` of many rows on a table with compressed keys where MySQL scanned the index to find the rows.

- Fixed problem with `CHECK` on table with deleted keyblocks.

- Fixed a bug in reconnect (at the client side) where it didn't free memory properly in some contexts.

- Fixed problems in update log when using `LAST_INSERT_ID()` to update a table with an `AUTO_INCREMENT` key.

- Added `NULLIF()` function.

- Fixed bug when using `LOAD DATA INFILE` on a table with `BLOB/TEXT` columns.

- Optimized `MyISAM` to be faster when inserting keys in sorted order.

- `EXPLAIN SELECT ...` now also prints out whether MySQL needs to create a temporary table or use file sorting when resolving the `SELECT`.

- Added optimization to skip `ORDER BY` parts where the part is a constant expression in the `WHERE` part. Indexes can now be used even if the `ORDER BY` doesn't match the index exactly, as long as all the unused index parts and all the extra `ORDER BY` columns are constants in the `WHERE` clause. See Section 7.4.5, « Comment MySQL utilise les index ».

- `UPDATE` and `DELETE` on a whole unique key in the `WHERE` part are now faster than before.

- Changed `RAID_CHUNKSIZE` to be in 1024-byte increments.

- Fixed core dump in `LOAD_FILE(NULL)`.

### C.4.47. Changements de la version 3.23.14

- Added `mysqlbinlog` program for displaying binary log files in text format.

- Added `mysql_real_escape_string()` function to the MySQL C API.

- Fixed a bug in `CONCAT()` where one of the arguments was a function that returned a modified argument.

- Fixed a critical bug in `myisamchk`, where it updated the header in the index file when one only checked the table. This confused the `mysqld` daemon if it updated the same table at the same time. Now the status in the index file is only updated if one uses `--update-state`. With older `myisamchk` versions you should use `--read-only` when only checking tables, if there is the slightest chance that the `mysqld` server is working on the table at the same time!

- Fixed that `DROP TABLE` is logged in the update log.

- Fixed problem when searching on `DECIMAL()` key field where the column data contained leading zeros.

- Fix bug in `myisamchk` when the `AUTO_INCREMENT` column isn't the first key.

- Allow `DATETIME` in ISO8601 format: 2000-03-12T12:00:00

- Dynamic character sets. A `mysqld` binary can now handle many different character sets (you can choose which when starting `mysqld`).

- Added command `REPAIR TABLE`.

- Added `mysql_thread_safe()` function to the MySQL C API.

- Added the `UMASK_DIR` environment variable.

- Added `CONNECTION_ID()` function to return the client connection thread ID.

- When using `=` on `BLOB` or `VARCHAR BINARY` keys, where only a part of the column was indexed, the whole column of the result row wasn't compared.

- Fix for `sjis` character set and `ORDER BY`.

- When running in ANSI mode, don't allow columns to be used that aren't in the `GROUP BY` part.

### C.4.48. Changements de la version 3.23.13

- Fixed problem when doing locks on the same table more than 2 times in the same `LOCK TABLE` command; this fixed the problem one got when running the test-ATIS test with `--fast` or `--check-only-changed`.

- Added `SQL_BUFFER_RESULT` option to `SELECT`.

- Removed end space from double/float numbers in results from temporary tables.

- Added `CHECK TABLE` command.

- Added changes for `MyISAM` in 3.23.12 that didn't get into the source distribution because of CVS problems.

- Fixed bug so that `mysqladmin shutdown` will wait for the local server to close down.

- Fixed a possible endless loop when calculating timestamp.

- Added `print_defaults` program to the `.rpm` files. Removed `mysqlbug` from the client `.rpm` file.

### C.4.49. Changements de la version 3.23.12 (07 mars 2000)

- Fixed bug in `MyISAM` involving `REPLACE ... SELECT ...` which could give a corrupted table.

- Fixed bug in `myisamchk` where it incorrectly reset the `AUTO_INCREMENT` value.

- LOTS of patches for Linux Alpha. MySQL now appears to be relatively stable on Alpha.

- Changed `DISTINCT` on `HEAP` temporary tables to use hashed keys to quickly find duplicated rows. This mostly concerns queries of type `SELECT DISTINCT ... GROUP BY ...`. This fixes a problem where not all duplicates were removed in queries of the above type. In addition, the new code is MUCH faster.

- Added patches to make MySQL compile on Mac OS X.

- Added `IF NOT EXISTS` clause to `CREATE DATABASE`.

- Added `--all-databases` and `--databases` options to `mysqldump` to allow dumping of many databases at the same time.

- Fixed bug in compressed `DECIMAL()` index in `MyISAM` tables.

- Fixed bug when storing 0 into a timestamp.

- When doing `mysqladmin shutdown` on a local connection, `mysqladmin` now waits until the PID file is gone before terminating.

- Fixed core dump with some `COUNT(DISTINCT ...)` queries.

- Fixed that `myisamchk` works properly with RAID tables.

- Fixed problem with `LEFT JOIN` and `key_field IS NULL`.

- Fixed bug in `net_clear()` which could give the error `Aborted connection` in the MySQL clients.

- Added options `USE INDEX (key_list)` and `IGNORE INDEX (key_list)` as parameters in `SELECT`.

- `DELETE` and `RENAME` should now work on `RAID` tables.

### C.4.50. Changements de la version 3.23.11

- Allow the `ALTER TABLE tbl_name ADD (field_list)` syntax.

- Fixed problem with optimizer that could sometimes use incorrect keys.

- Fixed that `GRANT/REVOKE ALL PRIVILEGES` doesn't affect `GRANT OPTION`.

- Removed extra ‘`)`’ from the output of `SHOW GRANTS`.

- Fixed problem when storing numbers in timestamps.

- Fix problem with timezones that have half hour offsets.

- Allow the syntax `UNIQUE INDEX` in `CREATE` statements.

- `mysqlhotcopy` - fast online hot-backup utility for local MySQL databases. By Tim Bunce.

- New more secure `mysqlaccess`. Thanks to Steve Harvey for this.

- Added `--i-am-a-dummy` and `--safe-updates` options to `mysql`.

- Added `select_limit` and `max_join_size` variables to `mysql`.

- Added `SQL_MAX_JOIN_SIZE` and `SQL_SAFE_UPDATES` options.

- Added `READ LOCAL` lock that doesn't lock the table for concurrent inserts. (This is used by `mysqldump`.)

- Changed that `LOCK TABLES ... READ` no longer allows concurrent inserts.

- Added `--skip-delay-key-write` option to `mysqld`.

- Fixed security problem in the protocol regarding password checking.

- `_rowid` can now be used as an alias for an integer type unique indexed column.

- Added back blocking of `SIGPIPE` when compiling with `--thread-safe-clients` to make things safe for old clients.

### C.4.51. Changements de la version 3.23.10

- Fixed bug in 3.23.9 where memory wasn't properly freed when using `LOCK TABLES`.

### C.4.52. Changements de la version 3.23.9

- Fixed problem that affected queries that did arithmetic on group functions.

- Fixed problem with timestamps and `INSERT DELAYED`.

- Fixed that `date_col BETWEEN const_date AND const_date` works.

- Fixed problem when only changing a 0 to `NULL` in a table with `BLOB/TEXT` columns.

- Fixed bug in range optimizer when using many key parts and or on the middle key parts: `WHERE K1=1 and K3=2 and (K2=2 and K4=4 or K2=3 and K4=5)`

- Added `source` command to `mysql` to allow reading of batch files inside the `mysql` client. Original patch by Matthew Vanecek.

- Fixed critical problem with the `WITH GRANT OPTION` option.

- Don't give an unnecessary `GRANT` error when using tables from many databases in the same query.

- Added VIO wrapper (needed for SSL support; by Andrei Errapart and Tõnu Samuel).

- Fixed optimizer problem on `SELECT` when using many overlapping indexes. MySQL should now be able to choose keys even better when there are many keys to choose from.

- Changed optimizer to prefer a range key instead of a ref key when the range key can uses more columns than the ref key (which only can use columns with `=`). For example, the following type of queries should now be faster: `SELECT * from key_part_1=const and key_part_2 > const2`

- Fixed bug that a change of all `VARCHAR` columns to `CHAR` columns didn't change row type from dynamic to fixed.

- Disabled floating-point exceptions for FreeBSD to fix core dump when doing `SELECT FLOOR(POW(2,63))`.

- Renamed `mysqld` startup option from `--delay-key-write` to `--delay-key-write-for-all-tables`.

- Added `read-next-on-key` to `HEAP` tables. This should fix all problems with `HEAP` tables when using non-`UNIQUE` keys.

- Added option to print default arguments to all clients.

- Added `--log-slow-queries` option to `mysqld` to log all queries that take a long time to a separate log file with a time indicating how long the query took.

- Fixed core dump when doing `WHERE key_col=RAND(...)`.

- Fixed optimization bug in `SELECT ... LEFT JOIN ... key_col IS NULL`, when `key_col` could contain `NULL` values.

- Fixed problem with 8-bit characters as separators in `LOAD DATA INFILE`.

### C.4.53. Changements de la version 3.23.8 (02 janvier 2000)

- Fixed problem when handling indexfiles larger than 8G.

- Added latest patches to MIT-pthreads for NetBSD.

- Fixed problem with timezones that are < GMT - 11.

- Fixed a bug when deleting packed keys in `NISAM`.

- Fixed problem with `ISAM` when doing some `ORDER BY ... DESC` queries.

- Fixed bug when doing a join on a text key which didn't cover the whole key.

- Option `--delay-key-write` didn't enable delayed key writing.

- Fixed update of `TEXT` column which involved only case changes.

- Fixed that `INSERT DELAYED` doesn't update timestamps that are given.

- Added function `YEARWEEK()` and options `x`, `X`, `v` and `V` to `DATE_FORMAT()`.

- Fixed problem with `MAX(indexed_column)` and `HEAP` tables.

- Fixed problem with `BLOB NULL` keys and `LIKE "prefix%"`.

- Fixed problem with `MyISAM` and fixed-length rows < 5 bytes.

- Fixed problem that could cause MySQL to touch freed memory when doing very complicated `GROUP BY` queries.

- Fixed core dump if you got a crashed table where an `ENUM` field value was too big.

### C.4.54. Changements de la version 3.23.7 (10 décembre 1999)

- Fixed workaround under Linux to avoid problems with `pthread_mutex_timedwait()`, which is used with `INSERT DELAYED`. See Section 2.8.1, « Notes relatives à Linux (toutes versions) ».

- Fixed that one will get a 'disk full' error message if one gets disk full when doing sorting (instead of waiting until we got more disk space).

- Fixed a bug in `MyISAM` with keys > 250 characters.

- In `MyISAM` one can now do an `INSERT` at the same time as other threads are reading from the table.

- Added `max_write_lock_count` variable to `mysqld` to force a `READ` lock after a certain number of `WRITE` locks.

- Inverted flag `delay_key_write` on `show variables`.

- Renamed `concurrency` variable to `thread_concurrency`.

- The following functions are now multi-byte-safe: `LOCATE(substr,str)`, `POSITION(substr IN str)`, `LOCATE(substr,str,pos)`, `INSTR(str,substr)`, `LEFT(str,len)`, `RIGHT(str,len)`, `SUBSTRING(str,pos,len)`, `SUBSTRING(str FROM pos FOR len)`, `MID(str,pos,len)`, `SUBSTRING(str,pos)`, `SUBSTRING(str FROM pos)`, `SUBSTRING_INDEX(str,delim,count)`, `RTRIM(str)`, `TRIM([[BOTH | TRAILING] [remstr] FROM] str)`, `REPLACE(str,from_str,to_str)`, `REVERSE(str)`, `INSERT(str,pos,len,newstr)`, `LCASE(str)`, `LOWER(str)`, `UCASE(str)` and `UPPER(str)`; patch by Wei He.

- Fix core dump when releasing a lock from a non-existent table.

- Remove locks on tables before starting to remove duplicates.

- Added option `FULL` to `SHOW PROCESSLIST`.

- Added option `--verbose` to `mysqladmin`.

- Fixed problem when automatically converting `HEAP` to `MyISAM`.

- Fixed bug in `HEAP` tables when doing insert + delete + insert + scan the table.

- Fixed bugs on Alpha with `REPLACE()` and `LOAD DATA INFILE`.

- Added `interactive_timeout` variable to `mysqld`.

- Changed the argument to `mysql_data_seek()` from `ulong` to `ulonglong`.

### C.4.55. Changements de la version 3.23.6

- Added `-O lower_case_table_names={0|1}` option to `mysqld` to allow users to force table names to lowercase.

- Added `SELECT ... INTO DUMPFILE`.

- Added `--ansi` option to `mysqld` to make some functions SQL-99 compatible.

- Temporary table names now start with `#sql`.

- Added quoting of identifiers with ``` (`"` in `--ansi` mode).

- Changed to use `snprintf()` when printing floats to avoid some buffer overflows on FreeBSD.

- Made `FLOOR()` overflow safe on FreeBSD.

- Added `--quote-names` option to `mysqldump`.

- Fixed bug that one could make a part of a `PRIMARY KEY NOT NULL`.

- Fixed `encrypt()` to be thread-safe and not reuse buffer.

- Added `mysql_odbc_escape_string()` function to support big5 characters in MyODBC.

- Rewrote the storage engine to use classes. This introduces a lot of new code, but will make table handling faster and better.

- Added patch by Sasha for user-defined variables.

- Changed that `FLOAT` and `DOUBLE` (without any length modifiers) no longer are fixed decimal point numbers.

- Changed the meaning of `FLOAT(X)`: Now this is the same as `FLOAT` if `X` <= 24 and a `DOUBLE` if 24 < `X` <= 53.

- `DECIMAL(X)` is now an alias for `DECIMAL(X,0)` and `DECIMAL` is now an alias for `DECIMAL(10,0)`. The same goes for `NUMERIC`.

- Added option `ROW_FORMAT={DEFAULT | DYNAMIC | FIXED | COMPRESSED}` to `CREATE_TABLE`.

- `DELETE FROM table_name` didn't work on temporary tables.

- Changed function `CHAR_LENGTH()` to be multi-byte character safe.

- Added function `ORD(string)`.

### C.4.56. Changements de la version 3.23.5 (20 octobre 1999)

- Fixed some Y2K problems in the new date handling in 3.23.

- Fixed problem with `SELECT DISTINCT ... ORDER BY RAND()`.

- Added patches by Sergei A. Golubchik for text searching on the `MyISAM` level.

- Fixed cache overflow problem when using full joins without keys.

- Fixed some configure issues.

- Some small changes to make parsing faster.

- Adding a column after the last field with `ALTER TABLE` didn't work.

- Fixed problem when using an `AUTO_INCREMENT` column in two keys

- With `MyISAM`, you now can have an `AUTO_INCREMENT` column as a key sub part: `CREATE TABLE foo (a INT NOT NULL AUTO_INCREMENT, b CHAR(5), PRIMARY KEY (b,a))`

- Fixed bug in `MyISAM` with packed char keys that could be `NULL`.

- `AS` on field name with `CREATE TABLE table_name SELECT ...` didn't work.

- Allow use of `NATIONAL` and `NCHAR` when defining character columns. This is the same as not using `BINARY`.

- Don't allow `NULL` columns in a `PRIMARY KEY` (only in `UNIQUE` keys).

- Clear `LAST_INSERT_ID()` if one uses this in ODBC: `WHERE auto_increment_column IS NULL`. This seems to fix some problems with Access.

- `SET SQL_AUTO_IS_NULL=0|1` now turns on/off the handling of searching after the last inserted row with `WHERE auto_increment_column IS NULL`.

- Added new variable `concurrency` to `mysqld` for Solaris.

- Added `--relative` option to `mysqladmin` to make `extended-status` more useful to monitor changes.

- Fixed bug when using `COUNT(DISTINCT ...)` on an empty table.

- Added support for the Chinese character set GBK.

- Fixed problem with `LOAD DATA INFILE` and `BLOB` columns.

- Added bit operator `~` (negation).

- Fixed problem with `UDF` functions.

### C.4.57. Changements de la version 3.23.4 (28 septembre 1999)

- Inserting a `DATETIME` into a `TIME` column no longer will try to store 'days' in it.

- Fixed problem with storage of float/double on little endian machines. (This affected `SUM()`.)

- Added connect timeout on TCP/IP connections.

- Fixed problem with `LIKE "%"` on an index that may have `NULL` values.

- `REVOKE ALL PRIVILEGES` didn't revoke all privileges.

- Allow creation of temporary tables with same name as the original table.

- When granting a user a `GRANT` option for a database, he couldn't grant privileges to other users.

- New command: `SHOW GRANTS FOR user` (by Sinisa).

- New `date_add` syntax: `date/datetime + INTERVAL # interval_type`. By Joshua Chamas.

- Fixed privilege check for `LOAD DATA REPLACE`.

- Automatic fixing of broken include files on Solaris 2.7

- Some configure issues to fix problems with big filesystem detection.

- `REGEXP` is now case-insensitive if you use non-binary strings.

### C.4.58. Changements de la version 3.23.3

- Added patches for MIT-pthreads on NetBSD.

- Fixed range bug in `MyISAM`.

- `ASC` is now the default again for `ORDER BY`.

- Added `LIMIT` to `UPDATE`.

- Added `mysql_change_user()` function to the MySQL C API.

- Added character set to `SHOW VARIABLES`.

- Added support of `--[whitespace]` comments.

- Allow `INSERT into tbl_name VALUES ()`, that is, you may now specify an empty value list to insert a row in which each column is set to its default value.

- Changed `SUBSTRING(text FROM pos)` to conform to SQL-99. (Before this construct returned the rightmost `pos` characters.)

- `SUM()` with `GROUP BY` returned 0 on some systems.

- Changed output for `SHOW TABLE STATUS`.

- Added `DELAY_KEY_WRITE` option to `CREATE TABLE`.

- Allow `AUTO_INCREMENT` on any key part.

- Fixed problem with `YEAR(NOW())` and `YEAR(CURDATE())`.

- Added `CASE` construct.

- New function `COALESCE()`.

### C.4.59. Changements de la version 3.23.2 (09 août 1999)

- Fixed range optimizer bug: `SELECT * FROM table_name WHERE key_part1 >= const AND (key_part2 = const OR key_part2 = const)`. The bug was that some rows could be duplicated in the result.

- Running `myisamchk` without `-a` updated the index distribution incorrectly.

- `SET SQL_LOW_PRIORITY_UPDATES=1` was causing a parse error.

- You can now update index columns that are used in the `WHERE` clause. `UPDATE tbl_name SET KEY=KEY+1 WHERE KEY > 100`

- Date handling should now be a bit faster.

- Added handling of fuzzy dates (dates where day or month is 0), such as `'1999-01-00'`.

- Fixed optimization of `SELECT ... WHERE key_part1=const1 AND key_part_2=const2 AND key_part1=const4 AND key_part2=const4`; indextype should be `range` instead of `ref`.

- Fixed `egcs` 1.1.2 optimizer bug (when using `BLOB` values) on Linux Alpha.

- Fixed problem with `LOCK TABLES` combined with `DELETE FROM table`.

- `MyISAM` tables now allow keys on `NULL` and `BLOB/TEXT` columns.

- The following join is now much faster: `SELECT ... FROM t1 LEFT JOIN t2 ON ... WHERE t2.not_null_column IS NULL`.

- `ORDER BY` and `GROUP BY` can be done on functions.

- Changed handling of 'const_item' to allow handling of `ORDER BY RAND()`.

- Indexes are now used for `WHERE key_column = function`.

- Indexes are now used for `WHERE key_column = col_name` even if the columns are not identically packed.

- Indexes are now used for `WHERE col_name IS NULL`.

- Changed heap tables to be stored in low_byte_first order (to make it easy to convert to `MyISAM` tables)

- Automatic change of `HEAP` temporary tables to `MyISAM` tables in case of ``table is full'' errors.

- Added `--init-file=file_name` option to `mysqld`.

- Added `COUNT(DISTINCT value, [value, ...])`.

- `CREATE TEMPORARY TABLE` now creates a temporary table, in its own namespace, that is automatically deleted if connection is dropped.

- New reserved words (required for `CASE`): `CASE, THEN, WHEN, ELSE and END`.

- New functions `EXPORT_SET()` and `MD5()`.

- Support for the GB2312 Chinese character set.

### C.4.60. Changements de la version 3.23.1

- Fixed some compilation problems.

### C.4.61. Changements de la version 3.23.0 (05 Aug 1999: Alpha)

- A new storage engine library (`MyISAM`) with a lot of new features. See Section 14.1, « Le moteur de tables `MyISAM` ».

- You can create in-memory `HEAP` tables which are extremely fast for lookups.

- Support for big files (63-bit) on OSs that support big files.

- New function `LOAD_FILE(filename)` to get the contents of a file as a string value.

- New `<=>` operator that acts as `=` but returns TRUE if both arguments are `NULL`. This is useful for comparing changes between tables.

- Added the ODBC 3.0 `EXTRACT(interval FROM datetime)` function.

- Columns defined as `FLOAT(X)` are not rounded on storage and may be in scientific notation (1.0 E+10) when retrieved.

- `REPLACE` is now faster than before.

- Changed `LIKE` character comparison to behave as `=`; This means that `'e' LIKE 'é'` is now true. (If the line doesn't display correctly, the latter 'e' is a French 'e' with an acute accent above.)

- `SHOW TABLE STATUS` returns a lot of information about the tables.

- Added `LIKE` to the `SHOW STATUS` command.

- Added `Privileges` column to `SHOW COLUMNS`.

- Added `Packed` and `Comment` columns to `SHOW INDEX`.

- Added comments to tables (with `CREATE TABLE ... COMMENT "xxx"`).

- Added `UNIQUE`, as in `CREATE TABLE tbl_name (col INT not null UNIQUE)`

- New create syntax: `CREATE TABLE tbl_name SELECT ...`

- New create syntax: `CREATE TABLE IF NOT EXISTS ...`

- Allow creation of `CHAR(0)` columns.

- `DATE_FORMAT()` now requires ‘`%`’ before any format character.

- `DELAYED` is now a reserved word (sorry about that :( ).

- An example procedure is added: `analyse`, file: `sql_analyse.c`. This will describe the data in your query. Try the following:

      SELECT ... FROM ...
      WHERE ... PROCEDURE ANALYSE([max elements,[max memory]])

  This procedure is extremely useful when you want to check the data in your table!

- `BINARY` cast to force a string to be compared in case-sensitive fashion.

- Added `--skip-show-database` option to `mysqld`.

- Check whether a row has changed in an `UPDATE` now also works with `BLOB`/`TEXT` columns.

- Added the `INNER` join syntax. Note: This made `INNER` a reserved word!

- Added support for netmasks to the hostname in the MySQL grant tables. You can specify a netmask using the `IP/NETMASK` syntax.

- If you compare a `NOT NULL DATE/DATETIME` column with `IS NULL`, this is changed to a compare against `0` to satisfy some ODBC applications. (By `<shreeve@uci.edu>`.)

- `NULL IN (...)` now returns `NULL` instead of `0`. This will ensure that `null_column NOT IN (...)` doesn't match `NULL` values.

- Fix storage of floating-point values in `TIME` columns.

- Changed parsing of `TIME` strings to be more strict. Now the fractional second part is detected (and currently skipped). The following formats are supported:

  - [[DAYS] [H]H:]MM:]SS[.fraction]

  - [[[[[H]H]H]H]MM]SS[.fraction]

- Detect (and ignore) fractional second part from `DATETIME`.

- Added the `LOW_PRIORITY` attribute to `LOAD DATA INFILE`.

- The default index name now uses the same case as the column name on which the index name is based.

- Changed default number of connections to 100.

- Use bigger buffers when using `LOAD DATA INFILE`.

- `DECIMAL(x,y)` now works according to standard SQL.

- Added aggregate `UDF` functions. Thanks to Andreas F. Bobak (`<bobak@relog.ch>`) for this!

- `LAST_INSERT_ID()` is now updated for `INSERT INTO ... SELECT`.

- Some small changes to the join table optimizer to make some joins faster.

- `SELECT DISTINCT` is much faster; it uses the new `UNIQUE` functionality in `MyISAM`. One difference compared to MySQL 3.22 is that the output of `DISTINCT` is no longer sorted.

- All C client API macros are now functions to make shared libraries more reliable. Because of this, you can no longer call `mysql_num_fields()` on a `MYSQL` object, you must use `mysql_field_count()` instead.

- Added use of `LIBWRAP`; patch by Henning P. Schmiedehausen.

- Don't allow `AUTO_INCREMENT` for other than numerical columns.

- Using `AUTO_INCREMENT` will now automatically make the column `NOT NULL`.

- Show `NULL` as the default value for `AUTO_INCREMENT` columns.

- Added `SQL_BIG_RESULT`; `SQL_SMALL_RESULT` is now default.

- Added a shared library RPM. This enhancement was contributed by David Fox (`<dsfox@cogsci.ucsd.edu>`).

- Added `--enable-large-files` and `--disable-large-files` options to `configure`. See `configure.in` for some systems where this is automatically turned off because of broken implementations.

- Upgraded `readline` to 4.0.

- New `CREATE TABLE` options: `PACK_KEYS` and `CHECKSUM`.

- Added `--default-table-type` option to `mysqld`.

## C.5. Changements de la version 3.22.x (Old; discontinued)

The 3.22 version has faster and safer connect code than version 3.21, as well as a lot of new nice enhancements. As there aren't really any major changes, upgrading from 3.21 to 3.22 should be very easy and painless. See Section 2.6.5, « Passer de la version 3.21 à la version 3.22 ».

### C.5.1. Changements de la version 3.22.35

- Fixed problem with `STD()`.

- Merged changes from the newest `ISAM` library from 3.23.

- Fixed problem with `INSERT DELAYED`.

- Fixed a bug core dump when using a `LEFT JOIN`/`STRAIGHT_JOIN` on a table with only one row.

### C.5.2. Changements de la version 3.22.34

- Fixed problem with `GROUP BY` on `TINYBLOB` columns; this caused bugzilla to not show rows in some queries.

- Had to do total recompile of the Windows binary version as VC++ didn't compile all relevant files for 3.22.33 :(

### C.5.3. Changements de la version 3.22.33

- Fixed problems in Windows when locking tables with `LOCK TABLE`.

- Quicker kill of `SELECT DISTINCT` queries.

### C.5.4. Changements de la version 3.22.32 (14 février 2000)

- Fixed problem when storing numbers in timestamps.

- Fix problem with timezones that have half hour offsets.

- Added `mysqlhotcopy`, a fast online hot-backup utility for local MySQL databases. By Tim Bunce.

- New more secure `mysqlaccess`. Thanks to Steve Harvey for this.

- Fixed security problem in the protocol regarding password checking.

- Fixed problem that affected queries that did arithmetic on `GROUP` functions.

- Fixed a bug in the `ISAM` code when deleting rows on tables with packed indexes.

### C.5.5. Changements de la version 3.22.31

- A few small fixes for the Windows version.

### C.5.6. Changements de la version 3.22.30

- Fixed optimizer problem on `SELECT` when using many overlapping indexes.

- Disabled floating-point exceptions for FreeBSD to fix core dump when doing `SELECT FLOOR(POW(2,63))`.

- Added print of default arguments options to all clients.

- Fixed critical problem with the `WITH GRANT OPTION` option.

- Fixed non-critical Y2K problem when writing short date to log files.

### C.5.7. Changements de la version 3.22.29 (02 janvier 2000)

- Upgraded the configure and include files to match the latest 3.23 version. This should increase portability and make it easier to build shared libraries.

- Added latest patches to MIT-pthreads for NetBSD.

- Fixed problem with timezones that are < GMT -11.

- Fixed a bug when deleting packed keys in NISAM.

- Fixed problem that could cause MySQL to touch freed memory when doing very complicated `GROUP BY` queries.

- Fixed core dump if you got a crashed table where an `ENUM` field value was too big.

- Added `mysqlshutdown.exe` and `mysqlwatch.exe` to the Windows distribution.

- Fixed problem when doing `ORDER BY` on a reference key.

- Fixed that `INSERT DELAYED` doesn't update timestamps that are given.

### C.5.8. Changements de la version 3.22.28 (20 octobre 1999)

- Fixed problem with `LEFT JOIN` and `COUNT()` on a column which was declared `NULL` + and it had a `DEFAULT` value.

- Fixed core dump problem when using `CONCAT()` in a `WHERE` clause.

- Fixed problem with `AVG()` and `STD()` with `NULL` values.

### C.5.9. Changements de la version 3.22.27

- Fixed prototype in `my_ctype.h` when using other character sets.

- Some configure issues to fix problems with big filesystem detection.

- Fixed problem when sorting on big `BLOB` columns.

- `ROUND()` will now work on Windows.

### C.5.10. Changements de la version 3.22.26 (16 septembre 1999)

- Fixed core dump with empty `BLOB/TEXT` column argument to `REVERSE()`.

- Extended `/*! */` with version numbers.

- Changed `SUBSTRING(text FROM pos)` to conform to SQL-99. (Before this construct returned the rightmost 'pos' characters.)

- Fixed problem with `LOCK TABLES` combined with `DELETE FROM table`

- Fixed problem that `INSERT ... SELECT` didn't use `BIG_TABLES`.

- `SET SQL_LOW_PRIORITY_UPDATES=#` didn't work.

- Password wasn't updated correctly if privileges didn't change on: `GRANT ... IDENTIFIED BY`

- Fixed range optimizer bug in `SELECT * FROM table_name WHERE key_part1 >= const AND (key_part2 = const OR key_part2 = const)`.

- Fixed bug in compression key handling in `ISAM`.

### C.5.11. Changements de la version 3.22.25

- Fixed some small problems with the installation.

### C.5.12. Changements de la version 3.22.24 (05 juillet 1999)

- `DATA` is no longer a reserved word.

- Fixed optimizer bug with tables with only one row.

- Fixed bug when using `LOCK TABLES table_name READ; FLUSH TABLES;`

- Applied some patches for HP-UX.

- `isamchk` should now work on Windows.

- Changed `configure` to not use big file handling on Linux as this crashes some Red Hat 6.0 systems

### C.5.13. Changements de la version 3.22.23 (08 juin 1999)

- Upgraded to use Autoconf 2.13, Automake 1.4 and `libtool` 1.3.2.

- Better support for SCO in `configure`.

- Added option `--defaults-file=file_name` to option file handling to force use of only one specific option file.

- Extended `CREATE` syntax to ignore MySQL Version 3.23 keywords.

- Fixed deadlock problem when using `INSERT DELAYED` on a table locked with `LOCK TABLES`.

- Fixed deadlock problem when using `DROP TABLE` on a table that was locked by another thread.

- Add logging of `GRANT/REVOKE` commands in the update log.

- Fixed `isamchk` to detect a new error condition.

- Fixed bug in `NATURAL LEFT JOIN`.

### C.5.14. Changements de la version 3.22.22 (30 avril 1999)

- Fixed problem in the C API when you called `mysql_close()` directly after `mysql_init()`.

- Better client error message when you can't open socket.

- Fixed `delayed_insert_thread` counting when you couldn't create a new delayed_insert thread.

- Fixed bug in `CONCAT()` with many arguments.

- Added patches for DEC 3.2 and SCO.

- Fixed path-bug when installing MySQL as a service on NT.

- MySQL on Windows is now compiled with VC++ 6.0 instead of with VC++ 5.0.

- New installation setup for MySQL on Windows.

### C.5.15. Changements de la version 3.22.21

- Fixed problem with `DELETE FROM TABLE` when table was locked by another thread.

- Fixed bug in `LEFT JOIN` involving empty tables.

- Changed the `mysql.db` column from `CHAR(32)` to `CHAR(60)`.

- `MODIFY` and `DELAYED` are no longer reserved words.

- Fixed a bug when storing days in a `TIME` column.

- Fixed a problem with `Host '...' is not allowed to connect to this MySQL server` after one had inserted a new MySQL user with a `GRANT` command.

- Changed to use `TCP_NODELAY` also on Linux (should give faster TCP/IP connections).

### C.5.16. Changements de la version 3.22.20 (18 mars 1999)

- Fixed `STD()` for big tables when result should be 0.

- The update log didn't have newlines on some operating systems.

- `INSERT DELAYED` had some garbage at end in the update log.

### C.5.17. Changements de la version 3.22.19 (Mar 1999: Production)

- Fixed bug in `mysql_install_db` (from 3.22.17).

- Changed default key cache size to 8M.

- Fixed problem with queries that needed temporary tables with `BLOB` columns.

### C.5.18. Changements de la version 3.22.18

- Fixes a fatal problem in 3.22.17 on Linux; after `shutdown` not all threads died properly.

- Added option `-O flush_time=#` to `mysqld`. This is mostly useful on Windows and tells how often MySQL should close all unused tables and flush all updated tables to disk.

- Fixed problem that a `VARCHAR` column compared with `CHAR` column didn't use keys efficiently.

### C.5.19. Changements de la version 3.22.17

- Fixed a core dump problem when using `--log-update` and connecting without a default database.

- Fixed some `configure` and portability problems.

- Using `LEFT JOIN` on tables that had circular dependencies caused `mysqld` to hang forever.

### C.5.20. Changements de la version 3.22.16 (Feb 1999: Gamma)

- `mysqladmin processlist` could kill the server if a new user logged in.

- `DELETE FROM tbl_name WHERE key_column=col_name` didn't find any matching rows. Fixed.

- `DATE_ADD(column, ...)` didn't work.

- `INSERT DELAYED` could deadlock with status `upgrading lock`.

- Extended `ENCRYPT()` to take longer salt strings than 2 characters.

- `longlong2str` is now much faster than before. For `Intel x86` platforms, this function is written in optimized assembler.

- Added the `MODIFY` keyword to `ALTER TABLE`.

### C.5.21. Changements de la version 3.22.15

- `GRANT` used with `IDENTIFIED BY` didn't take effect until privileges were flushed.

- Name change of some variables in `SHOW STATUS`.

- Fixed problem with `ORDER BY` with 'only index' optimization when there were multiple key definitions for a used column.

- `DATE` and `DATETIME` columns are now up to 5 times faster than before.

- `INSERT DELAYED` can be used to let the client do other things while the server inserts rows into a table.

- `LEFT JOIN USING (col1,col2)` didn't work if one used it with tables from 2 different databases.

- `LOAD DATA LOCAL INFILE` didn't work in the Unix version because of a missing file.

- Fixed problems with `VARCHAR`/`BLOB` on very short rows (< 4 bytes); error 127 could occur when deleting rows.

- Updating `BLOB/TEXT` through formulas didn't work for short (< 256 char) strings.

- When you did a `GRANT` on a new host, `mysqld` could die on the first connect from this host.

- Fixed bug when one used `ORDER BY` on column name that was the same name as an alias.

- Added `BENCHMARK(loop_count,expression)` function to time expressions.

### C.5.22. Changements de la version 3.22.14

- Allow empty arguments to `mysqld` to make it easier to start from shell scripts.

- Setting a `TIMESTAMP` column to `NULL` didn't record the timestamp value in the update log.

- Fixed lock handler bug when one did `INSERT INTO TABLE ... SELECT ... GROUP BY`.

- Added a patch for `localtime_r()` on Windows so that it will no lonher crash if your date is > 2039, but instead will return a time of all zero.

- Names for user-defined functions are no longer case-sensitive.

- Added escape of `^Z` (ASCII 26) to `\Z` as `^Z` doesn't work with pipes on Windows.

- `mysql_fix_privileges` adds a new column to the `mysql.func` to support aggregate `UDF` functions in future MySQL releases.

### C.5.23. Changements de la version 3.22.13

- Saving `NOW()`, `CURDATE()` or `CURTIME()` directly in a column didn't work.

- `SELECT COUNT(*) ... LEFT JOIN ...` didn't work with no `WHERE` part.

- Updated `config.guess` to allow MySQL to configure on UnixWare 7.1.x.

- Changed the implementation of `pthread_cond()` on the Windows version. `get_lock()` now correctly times out on Windows!

### C.5.24. Changements de la version 3.22.12

- Fixed problem when using `DATE_ADD()` and `DATE_SUB()` in a `WHERE` clause.

- You can now set the password for a user with the `GRANT ... TO user IDENTIFIED BY 'password'` syntax.

- Fixed bug in `GRANT` checking with `SELECT` on many tables.

- Added missing file `mysql_fix_privilege_tables` to the RPM distribution. This is not run by default because it relies on the client package.

- Added option `SQL_SMALL_RESULT` to `SELECT` to force use of fast temporary tables when you know that the result set will be small.

- Allow use of negative real numbers without a decimal point.

- Day number is now adjusted to maximum days in month if the resulting month after `DATE_ADD`/`DATE_SUB()` doesn't have enough days.

- Fix that `GRANT` compares columns in case-insensitive fashion.

- Fixed a bug in `sql_list.h` that made `ALTER TABLE` dump core in some contexts.

- The hostname in `user@hostname` can now include ‘`.`’ and ‘`-`’ without quotes in the context of the `GRANT`, `REVOKE` and `SET PASSWORD FOR ...` statements.

- Fix for `isamchk` for tables which need big temporary files.

### C.5.25. Changements de la version 3.22.11

- Important: You must run the `mysql_fix_privilege_tables` script when you upgrade to this version! This is needed because of the new `GRANT` system. If you don't do this, you will get `Access denied` when you try to use `ALTER TABLE`, `CREATE INDEX`, or `DROP INDEX`.

- `GRANT` to allow/deny users table and column access.

- Changed `USER()` to return a value in `user@host` format. Formerly it returned only `user`.

- Changed the syntax for how to set `PASSWORD` for another user.

- New command `FLUSH STATUS` that resets most status variables to zero.

- New status variables: `aborted_threads`, `aborted_connects`.

- New option variable: `connection_timeout`.

- Added support for Thai sorting (by Pruet Boonma `<pruet@ds90.intanon.nectec.or.th>`).

- Slovak and Japanese error messages.

- Configuration and portability fixes.

- Added option `SET SQL_WARNINGS=1` to get a warning count also for simple (single-row) inserts.

- MySQL now uses `SIGTERM` instead of `SIGQUIT` with shutdown to work better on FreeBSD.

- Added option `\G` (print vertically) to `mysql`.

- `SELECT HIGH_PRIORITY ...` killed `mysqld`.

- `IS NULL` on a `AUTO_INCREMENT` column in a `LEFT JOIN` didn't work as expected.

- New function `MAKE_SET()`.

### C.5.26. Changements de la version 3.22.10

- `mysql_install_db` no longer starts the MySQL server! You should start `mysqld` with `safe_mysqld` after installing it! The MySQL `RPM` will, however, start the server as before.

- Added `--bootstrap` option to `mysqld` and recoded `mysql_install_db` to use it. This will make it easier to install MySQL with `RPM`s.

- Changed `+`, `-` (sign and minus), `*`, `/`, `%`, `ABS()` and `MOD()` to be `BIGINT` aware (64-bit safe).

- Fixed a bug in `ALTER TABLE` that caused `mysqld` to crash.

- MySQL now always reports the conflicting key values when a duplicate key entry occurs. (Before this was only reported for `INSERT`.)

- New syntax: `INSERT INTO tbl_name SET col_name=value, col_name=value, ...`

- Most errors in the `.err` log are now prefixed with a time stamp.

- Added option `MYSQL_INIT_COMMAND` to `mysql_options()` to make a query on connect or reconnect.

- Added option `MYSQL_READ_DEFAULT_FILE` and `MYSQL_READ_DEFAULT_GROUP` to `mysql_options()` to read the following parameters from the MySQL option files: `port`, `socket`, `compress`, `password`, `pipe`, `timeout`, `user`, `init-command`, `host` and `database`.

- Added `maybe_null` to the `UDF` structure.

- Added option `IGNORE` to `INSERT` statements with many rows.

- Fixed some problems with sorting of the `koi8` character sets; users of `koi8` must run `isamchk -rq` on each table that has an index on a `CHAR` or `VARCHAR` column.

- New script `mysql_setpermission`, by Luuk de Boer. It allows easy creation of new users with permissions for specific databases.

- Allow use of hexadecimal strings (0x...) when specifying a constant string (like in the column separators with `LOAD DATA INFILE`).

- Ported to OS/2 (thanks to Antony T. Curtis `<antony.curtis@olcs.net>`).

- Added more variables to `SHOW STATUS` and changed format of output to be like `SHOW VARIABLES`.

- Added `extended-status` command to `mysqladmin` which will show the new status variables.

### C.5.27. Changements de la version 3.22.9

- `SET SQL_LOG_UPDATE=0` caused a lockup of the server.

- New SQL command: `FLUSH [ TABLES | HOSTS | LOGS | PRIVILEGES ] [, ...]`

- New SQL command: `KILL` `thread_id`.

- Added casts and changed include files to make MySQL easier to compile on AIX and DEC OSF/1 4.x

- Fixed conversion problem when using `ALTER TABLE` from a `INT` to a short `CHAR()` column.

- Added `SELECT HIGH_PRIORITY`; this will get a lock for the `SELECT` even if there is a thread waiting for another `SELECT` to get a `WRITE LOCK`.

- Moved `wild_compare()` to string class to be able to use `LIKE` on `BLOB`/`TEXT` columns with `\0`.

- Added `ESCAPE` option to `LIKE`.

- Added a lot more output to `mysqladmin debug`.

- You can now start `mysqld` on Windows with the `--flush` option. This will flush all tables to disk after each update. This makes things much safer on the Windows platforms but also much slower.

### C.5.28. Changements de la version 3.22.8

- Czech character sets should now work much better.

- `DATE_ADD()` and `DATE_SUB()` didn't work with group functions.

- `mysql` will now also try to reconnect on `USE database` commands.

- Fix problem with `ORDER BY` and `LEFT JOIN` and `const` tables.

- Fixed problem with `ORDER BY` if the first `ORDER BY` column was a key and the rest of the `ORDER BY` columns wasn't part of the key.

- Fixed a big problem with `OPTIMIZE TABLE`.

- MySQL clients on NT will now by default first try to connect with named pipes and after this with TCP/IP.

- Fixed a problem with `DROP TABLE` and `mysqladmin shutdown` on Windows (a fatal bug from 3.22.6).

- Fixed problems with `TIME columns` and negative strings.

- Added an extra thread signal loop on shutdown to avoid some error messages from the client.

- MySQL now uses the next available number as extension for the update log file.

- Added patches for UNIXWARE 7.

### C.5.29. Changements de la version 3.22.7 (Sep 1998: Beta)

- Added `LIMIT` clause for the `DELETE` statement.

- You can now use the `/*! ... */` syntax to hide MySQL-specific keywords when you write portable code. MySQL will parse the code inside the comments as if the surrounding `/*!` and `*/` comment characters didn't exist.

- `OPTIMIZE TABLE tbl_name` can now be used to reclaim disk space after many deletes. Currently, this uses `ALTER TABLE` to regenerate the table, but in the future it will use an integrated `isamchk` for more speed.

- Upgraded `libtool` to get the configure more portable.

- Fixed slow `UPDATE` and `DELETE` operations when using `DATETIME` or `DATE` keys.

- Changed optimizer to make it better at deciding when to do a full join and when using keys.

- You can now use `mysqladmin proc` to display information about your own threads. Only users with the `PROCESS` privilege can get information about all threads. (In 4.0.2 one needs the `SUPER` privilege for this.)

- Added handling of formats `YYMMDD`, `YYYYMMDD`, `YYMMDDHHMMSS` for numbers when using `DATETIME` and `TIMESTAMP` types. (Formerly these formats only worked with strings.)

- Added connect option `CLIENT_IGNORE_SPACE` to allow use of spaces after function names and before ‘`(`’ (Powerbuilder requires this). This will make all function names reserved words.

- Added the `--log-long-format` option to `mysqld` to enable timestamps and INSERT_IDs in the update log.

- Added `--where` option to `mysqldump` (patch by Jim Faucette).

- The lexical analyzer now uses ``perfect hashing'' for faster parsing of SQL statements.

### C.5.30. Changements de la version 3.22.6

- Faster `mysqldump`.

- For the `LOAD DATA INFILE` statement, you can now use the new `LOCAL` keyword to read the file from the client. `mysqlimport` will automatically use `LOCAL` when importing with the TCP/IP protocol.

- Fixed small optimize problem when updating keys.

- Changed makefiles to support shared libraries.

- MySQL-NT can now use named pipes, which means that you can now use MySQL-NT without having to install TCP/IP.

### C.5.31. Changements de la version 3.22.5

- All table lock handing is changed to avoid some very subtle deadlocks when using `DROP TABLE`, `ALTER TABLE`, `DELETE FROM TABLE` and `mysqladmin flush-tables` under heavy usage. Changed locking code to get better handling of locks of different types.

- Updated `DBI` to 1.00 and `DBD` to 1.2.0.

- Added a check that the error message file contains error messages suitable for the current version of `mysqld`. (To avoid errors if you accidentally try to use an old error message file.)

- All count structures in the client (`affected_rows()`, `insert_id()`, ...) are now of type `BIGINT` to allow 64-bit values to be used. This required a minor change in the MySQL protocol which should affect only old clients when using tables with `AUTO_INCREMENT` values > 16M.

- The return type of `mysql_fetch_lengths()` has changed from `uint *` to `ulong *`. This may give a warning for old clients but should work on most machines.

- Change `mysys` and `dbug` libraries to allocate all thread variables in one struct. This makes it easier to make a threaded `libmysql.dll` library.

- Use the result from `gethostname()` (instead of `uname()`) when constructing `.pid` file names.

- New better compressed server/client protocol.

- `COUNT()`, `STD()` and `AVG()` are extended to handle more than 4G rows.

- You can now store values in the range `-838:59:59` <= x <= `838:59:59` in a `TIME` column.

- Warning: incompatible change!! If you set a `TIME` column to too short a value, MySQL now assumes the value is given as: `[[[D ]HH:]MM:]SS` instead of `HH[:MM[:SS]]`.

- `TIME_TO_SEC()` and `SEC_TO_TIME()` can now handle negative times and hours up to 32767.

- Added new option `SET SQL_LOG_UPDATE={0|1}` to allow users with the `PROCESS` privilege to bypass the update log. (Modified patch from Sergey A Mukhin `<violet@rosnet.net>`.)

- Fixed fatal bug in `LPAD()`.

- Initialize line buffer in `mysql.cc` to make `BLOB` reading from pipes safer.

- Added `-O max_connect_errors=#` option to `mysqld`. Connect errors are now reset for each correct connection.

- Increased the default value of `max_allowed_packet` to `1M` in `mysqld`.

- Added `--low-priority-updates` option to `mysqld`, to give table-modifying operations (`INSERT`, `REPLACE`, `UPDATE`, `DELETE`) lower priority than retrievals. You can now use `{INSERT | REPLACE | UPDATE | DELETE} LOW_PRIORITY ...` You can also use `SET SQL_LOW_PRIORITY_UPDATES={0|1}` to change the priority for one thread. One side effect is that `LOW_PRIORITY` is now a reserved word. :(

- Add support for `INSERT INTO table ... VALUES(...),(...),(...)`, to allow inserting multiple rows with a single statement.

- `INSERT INTO tbl_name` is now also cached when used with `LOCK TABLES`. (Previously only `INSERT ... SELECT` and `LOAD DATA INFILE` were cached.)

- Allow `GROUP BY` functions with `HAVING`:

      mysql> SELECT col FROM table GROUP BY col HAVING COUNT(*)>0;

- `mysqld` will now ignore trailing ‘`;`’ characters in queries. This is to make it easier to migrate from some other SQL servers that require the trailing ‘`;`’.

- Fix for corrupted fixed-format output generated by `SELECT INTO OUTFILE`.

- Warning: incompatible change! Added Oracle `GREATEST()` and `LEAST()` functions. You must now use these instead of the `MAX()` and `MIN()` functions to get the largest/smallest value from a list of values. These can now handle `REAL`, `BIGINT` and string (`CHAR` or `VARCHAR`) values.

- Warning: incompatible change! `DAYOFWEEK()` had offset 0 for Sunday. Changed the offset to 1.

- Give an error for queries that mix `GROUP BY` columns and fields when there is no `GROUP BY` specification.

- Added `--vertical` option to `mysql`, for printing results in vertical mode.

- Index-only optimization; some queries are now resolved using only indexes. Until MySQL 4.0, this works only for numeric columns. See Section 7.4.5, « Comment MySQL utilise les index ».

- Lots of new benchmarks.

- A new C API chapter and lots of other improvements in the manual.

### C.5.32. Changements de la version 3.22.4

- Added `--tmpdir` option to `mysqld`, for specifying the location of the temporary file directory.

- MySQL now automatically changes a query from an ODBC client:

      SELECT ... FROM table WHERE auto_increment_column IS NULL

  to:

      SELECT ... FROM table WHERE auto_increment_column == LAST_INSERT_ID()

  This allows some ODBC programs (Delphi, Access) to retrieve the newly inserted row to fetch the `AUTO_INCREMENT` id.

- `DROP TABLE` now waits for all users to free a table before deleting it.

- Fixed small memory leak in the new connect protocol.

- New functions `BIN()`, `OCT()`, `HEX()` and `CONV()` for converting between different number bases.

- Added function `SUBSTRING()` with 2 arguments.

- If you created a table with a record length smaller than 5, you couldn't delete rows from the table.

- Added optimization to remove `const` reference tables from `ORDER BY` and `GROUP BY`.

- `mysqld` now automatically disables system locking on Linux and Windows, and for systems that use MIT-pthreads. You can force the use of locking with the `--enable-external-locking` option.

- Added `--console` option to `mysqld`, to force a console window (for error messages) when using Windows.

- Fixed table locks for Windows.

- Allow ‘`$`’ in identifiers.

- Changed name of user-specific configuration file from `my.cnf` to `.my.cnf` (Unix only).

- Added `DATE_ADD()` and `DATE_SUB()` functions.

### C.5.33. Changements de la version 3.22.3

- Fixed a lock problem (bug in MySQL Version 3.22.1) when closing temporary tables.

- Added missing `mysql_ping()` to the client library.

- Added `--compress` option to all MySQL clients.

- Changed `byte` to `char` in `mysql.h` and `mysql_com.h`.

### C.5.34. Changements de la version 3.22.2

- Searching on multiple constant keys that matched more than 30% of the rows didn't always use the best possible key.

- New functions `<<`, `>>`, `RPAD()` and `LPAD()`.

- You can now save default options (like passwords) in a configuration file (`my.cnf`).

- Lots of small changes to get `ORDER BY` to work when no records are found when using fields that are not in `GROUP BY` (MySQL extension).

- Added `--chroot` option to `mysqld`, to start `mysqld` in a chroot environment (by Nikki Chumakov `<nikkic@cityline.ru>`).

- Trailing spaces are now ignored when comparing case-sensitive strings; this should fix some problems with ODBC and flag 512!

- Fixed a core dump bug in the range optimizer.

- Added `--one-thread` option to `mysqld`, for debugging with `LinuxThreads` (or `glibc`). (This replaces the `-T32` flag)

- Added `DROP TABLE IF EXISTS` to prevent an error from occurring if the table doesn't exist.

- `IF` and `EXISTS` are now reserved words (they would have to be sooner or later).

- Added lots of new options to `mysqldump`.

- Server error messages are now in `mysqld_error.h`.

- The server/client protocol now supports compression.

- All bug fixes from MySQL Version 3.21.32.

### C.5.35. Changements de la version 3.22.1 (Jun 1998: Alpha)

- Added new C API function `mysql_ping()`.

- Added new API functions `mysql_init()` and `mysql_options()`. You now MUST call `mysql_init()` before you call `mysql_real_connect()`. You don't have to call `mysql_init()` if you only use `mysql_connect()`.

- Added `mysql_options(...,MYSQL_OPT_CONNECT_TIMEOUT,...)` so you can set a timeout for connecting to a server.

- Added `--timeout` option to `mysqladmin`, as a test of `mysql_options()`.

- Added `AFTER column` and `FIRST` options to `ALTER TABLE ... ADD columns`. This makes it possible to add a new column at some specific location within a row in an existing table.

- `WEEK()` now takes an optional argument to allow handling of weeks when the week starts on Monday (some European countries). By default, `WEEK()` assumes the week starts on Sunday.

- `TIME` columns weren't stored properly (bug in MySQL Version 3.22.0).

- `UPDATE` now returns information about how many rows were matched and updated, and how many ``warnings'' occurred when doing the update.

- Fixed incorrect result from `FORMAT(-100,2)`.

- `ENUM` and `SET` columns were compared in binary (case-sensitive) fashion; changed to be case-insensitive.

### C.5.36. Changements de la version 3.22.0

- New (backward-compatible) connect protocol that allows you to specify the database to use when connecting, to get much faster connections to a specific database.

  The `mysql_real_connect()` call is changed to:

      mysql_real_connect(MYSQL *mysql, const char *host, const char *user,
                         const char *passwd, const char *db, uint port,
                         const char *unix_socket, uint client_flag)

- Each connection is handled by its own thread, rather than by the master `accept()` thread. This fixes permanently the telnet bug that was a topic on the mail list some time ago.

- All TCP/IP connections are now checked with backward-resolution of the hostname to get better security. `mysqld` now has a local hostname resolver cache so connections should actually be faster than before, even with this feature.

- A site automatically will be blocked from future connections if someone repeatedly connects with an ``improper header'' (like when one uses telnet).

- You can now refer to tables in different databases with references of the form `tbl_name@db_name` or `db_name.tbl_name`. This makes it possible to give a user read access to some tables and write access to others simply by keeping them in different databases!

- Added `--user` option to `mysqld`, to allow it to run as another Unix user (if it is started as the Unix `root` user).

- Added caching of users and access rights (for faster access rights checking)

- Normal users (not anonymous ones) can change their password with `mysqladmin password "new_password"`. This uses encrypted passwords that are not logged in the normal MySQL log!

- All important string functions are now coded in assembler for x86 Linux machines. This gives a speedup of 10% in many cases.

- For tables that have many columns, the column names are now hashed for much faster column name lookup (this will speed up some benchmark tests a lot!)

- Some benchmarks are changed to get better individual timing. (Some loops were so short that a specific test took < 2 seconds. The loops have been changed to take about 20 seconds to make it easier to compare different databases. A test that took 1-2 seconds before now takes 11-24 seconds, which is much better)

- Re-arranged `SELECT` code to handle some very specific queries involving group functions (like `COUNT(*)`) without a `GROUP BY` but with `HAVING`. The following now works:

      mysql> SELECT COUNT(*) as C FROM table HAVING C > 1;

- Changed the protocol for field functions to be faster and avoid some calls to `malloc()`.

- Added `-T32` option to `mysqld`, for running all queries under the main thread. This makes it possible to debug `mysqld` under Linux with `gdb`!

- Added optimization of `not_null_column IS NULL` (needed for some Access queries).

- Allow `STRAIGHT_JOIN` to be used between two tables to force the optimizer to join them in a specific order.

- String functions now return `VARCHAR` rather than `CHAR` and the column type is now `VARCHAR` for fields saved as `VARCHAR`. This should make the `MyODBC` driver better, but may break some old MySQL clients that don't handle `FIELD_TYPE_VARCHAR` the same way as `FIELD_TYPE_CHAR`.

- `CREATE INDEX` and `DROP INDEX` are now implemented through `ALTER TABLE`. `CREATE TABLE` is still the recommended (fast) way to create indexes.

- Added `--set-variable` option `wait_timeout` to `mysqld`.

- Added time column to `mysqladmin processlist` to show how long a query has taken or how long a thread has slept.

- Added lots of new variables to `show variables` and some new to `show status`.

- Added new type `YEAR`. `YEAR` is stored in 1 byte with allowable values of 0, and 1901 to 2155.

- Added new `DATE` type that is stored in 3 bytes rather than 4 bytes. All new tables are created with the new date type if you don't use the `--old-protocol` option to `mysqld`.

- Fixed bug in record caches; for some queries, you could get `Error from table handler: #` on some operating systems.

- Added `--enable-assembler` option to `configure`, for x86 machines (tested on Linux + `gcc`). This will enable assembler functions for the most important string functions for more speed!

## C.6. Changements de la version 3.21.x

La version 3.21 est plutôt vieille, et doit être évitée si possible. Les informations de cette section sont conservées à des fins d'archives.

### C.6.1. Changements de la version 3.21.33

- Fixed problem when sending `SIGHUP` to `mysqld`; `mysqld` core dumped when starting from boot on some systems.

- Fixed problem with losing a little memory for some connections.

- `DELETE FROM tbl_name` without a `WHERE` condition is now done the long way when you use `LOCK TABLES` or if the table is in use, to avoid race conditions.

- `INSERT INTO TABLE (timestamp_column) VALUES (NULL);` didn't set timestamp.

### C.6.2. Changements de la version 3.21.32

- Fixed some possible race conditions when doing many reopen/close on the same tables under heavy load! This can happen if you execute `mysqladmin refresh` often. This could in some very rare cases corrupt the header of the index file and cause error 126 or 138.

- Fixed fatal bug in `refresh()` when running with the `--skip-external-locking` option. There was a ``very small'' time gap after a `mysqladmin refresh` when a table could be corrupted if one thread updated a table while another thread did `mysqladmin refresh` and another thread started a new update ont the same table before the first thread had finished. A refresh (or `--flush-tables`) will now not return until all used tables are closed!

- `SELECT DISTINCT` with a `WHERE` clause that didn't match any rows returned a row in some contexts (bug only in 3.21.31).

- `GROUP BY` + `ORDER BY` returned one empty row when no rows where found.

- Fixed a bug in the range optimizer that wrote `Use_count: Wrong count for ...` in the error log file.

### C.6.3. Changements de la version 3.21.31

- Fixed a sign extension problem for the `TINYINT` type on Irix.

- Fixed problem with `LEFT("constant_string",function)`.

- Fixed problem with `FIND_IN_SET()`.

- `LEFT JOIN` core dumped if the second table is used with a constant `WHERE/ON` expression that uniquely identifies one record.

- Fixed problems with `DATE_FORMAT()` and incorrect dates. `DATE_FORMAT()` now ignores `'%'` to make it possible to extend it more easily in the future.

### C.6.4. Changements de la version 3.21.30

- `mysql` now returns an exit code > 0 if the query returned an error.

- Saving of command-line history to file in `mysql` client. By Tommy Larsen `<tommy@mix.hive.no>`.

- Fixed problem with empty lines that were ignored in `mysql.cc`.

- Save the pid of the signal handler thread in the pid file instead of the pid of the main thread.

- Added patch by `<tommy@valley.ne.jp>` to support Japanese characters SJIS and UJIS.

- Changed `safe_mysqld` to redirect startup messages to `'hostname'.err` instead of `'hostname'.log` to reclaim file space on `mysqladmin refresh`.

- `ENUM` always had the first entry as default value.

- `ALTER TABLE` wrote two entries to the update log.

- `sql_acc()` now closes the `mysql` grant tables after a reload to save table space and memory.

- Changed `LOAD DATA` to use less memory with tables and `BLOB` columns.

- Sorting on a function which made a division / 0 produced a wrong set in some cases.

- Fixed `SELECT` problem with `LEFT()` when using the `czech` character set.

- Fixed problem in `isamchk`; it couldn't repair a packed table in a very unusual case.

- `SELECT` statements with `&` or `|` (bit functions) failed on columns with `NULL` values.

- When comparing a field = field, where one of the fields was a part key, only the length of the part key was compared.

### C.6.5. Changements de la version 3.21.29

- `LOCK TABLES` + `DELETE from tbl_name` never removed locks properly.

- Fixed problem when grouping on an `OR` function.

- Fixed permission problem with `umask()` and creating new databases.

- Fixed permission problem on result file with `SELECT ... INTO OUTFILE ...`

- Fixed problem in range optimizer (core dump) for a very complex query.

- Fixed problem when using `MIN(integer)` or `MAX(integer)` in `GROUP BY`.

- Fixed bug on Alpha when using integer keys. (Other keys worked on Alpha.)

- Fixed bug in `WEEK("XXXX-xx-01")`.

### C.6.6. Changements de la version 3.21.28

- Fixed socket permission (clients couldn't connect to Unix socket on Linux).

- Fixed bug in record caches; for some queries, you could get `Error from table handler: #` on some operating systems.

### C.6.7. Changements de la version 3.21.27

- Added user level lock functions `GET_LOCK(string,timeout)`, `RELEASE_LOCK(string)`.

- Added `Opened_tables` to `show status`.

- Changed connect timeout to 3 seconds to make it somewhat harder for crackers to kill `mysqld` through telnet + TCP/IP.

- Fixed bug in range optimizer when using `WHERE key_part_1 >= something AND key_part_2 <= something_else`.

- Changed `configure` for detection of FreeBSD 3.0 9803xx and above

- `WHERE` with `string_col_key = constant_string` didn't always find all rows if the column had many values differing only with characters of the same sort value (like e and e with an accent).

- Strings keys looked up with 'ref' were not compared in case-sensitive fashion.

- Added `umask()` to make log files non-readable for normal users.

- Ignore users with old (8-byte) password on startup if not using `--old-protocol` option to `mysqld`.

- `SELECT` which matched all key fields returned the values in the case of the matched values, not of the found values. (Minor problem.)

### C.6.8. Changements de la version 3.21.26

- `FROM_DAYS(0)` now returns "0000-00-00".

- In `DATE_FORMAT()`, PM and AM were swapped for hours 00 and 12.

- Extended the default maximum key size to 256.

- Fixed bug when using `BLOB`/`TEXT` in `GROUP BY` with many tables.

- An `ENUM` field that is not declared `NOT NULL` has `NULL` as the default value. (Previously, the default value was the first enumeration value.)

- Fixed bug in the join optimizer code when using many part keys on the same key: `INDEX (Organization,Surname(35),Initials(35))`.

- Added some tests to the table order optimizer to get some cases with `SELECT ... FROM many_tables` much faster.

- Added a retry loop around `accept()` to possibly fix some problems on some Linux machines.

### C.6.9. Changements de la version 3.21.25

- Changed `typedef 'string'` to `typedef 'my_string'` for better portability.

- You can now kill threads that are waiting on a disk-full condition.

- Fixed some problems with `UDF` functions.

- Added long options to `isamchk`. Try `isamchk --help`.

- Fixed a bug when using 8 bytes long (alpha); `filesort()` didn't work. Affects `DISTINCT`, `ORDER BY` and `GROUP BY` on 64-bit processors.

### C.6.10. Changements de la version 3.21.24

- Dynamic loadable functions. Based on source from Alexis Mikhailov.

- You couldn't delete from a table if no one had done a `SELECT` on the table.

- Fixed problem with range optimizer with many `OR` operators on key parts inside each other.

- Recoded `MIN()` and `MAX()` to work properly with strings and `HAVING`.

- Changed default umask value for new files from `0664` to `0660`.

- Fixed problem with `LEFT JOIN` and constant expressions in the `ON` part.

- Added Italian error messages from `<brenno@dewinter.com>`.

- `configure` now works better on OSF/1 (tested on 4.0D).

- Added hooks to allow `LIKE` optimization with international character support.

- Upgraded `DBI` to 0.93.

### C.6.11. Changements de la version 3.21.23

- The following symbols are now reserved words: `TIME`, `DATE`, `TIMESTAMP`, `TEXT`, `BIT`, `ENUM`, `NO`, `ACTION`, `CHECK`, `YEAR`, `MONTH`, `DAY`, `HOUR`, `MINUTE`, `SECOND`, `STATUS`, `VARIABLES`.

- Setting a `TIMESTAMP` to `NULL` in `LOAD DATA INFILE ...` didn't set the current time for the `TIMESTAMP`.

- Fix `BETWEEN` to recognize binary strings. Now `BETWEEN` is case-sensitive.

- Added `--skip-thread-priority` option to `mysqld`, for systems where `mysqld`'s thread scheduling doesn't work properly (BSDI 3.1).

- Added ODBC functions `DAYNAME()` and `MONTHNAME()`.

- Added function `TIME_FORMAT()`. This works like `DATE_FORMAT()`, but takes a time string (`'HH:MM:SS'`) as argument.

- Fixed unlikely(?) key optimizer bug when using `OR` operators of key parts inside `AND` expressions.

- Added `variables` command to `mysqladmin`.

- A lot of small changes to the binary releases.

- Fixed a bug in the new protocol from MySQL Version 3.21.20.

- Changed `ALTER TABLE` to work with Windows (Windows can't rename open files). Also fixed a couple of small bugs in the Windows version.

- All standard MySQL clients are now ported to MySQL for Windows.

- MySQL can now be started as a service on NT.

### C.6.12. Changements de la version 3.21.22

- Starting with this version, all MySQL distributions will be configured, compiled and tested with `crash-me` and the benchmarks on the following platforms: SunOS 5.6 sun4u, SunOS 5.5.1 sun4u, SunOS 4.14 sun4c, SunOS 5.6 i86pc, Irix 6.3 mips5k, HP-UX 10.20 hppa, AIX 4.2.1 ppc, OSF/1 V4.0 alpha, FreeBSD 2.2.2 i86pc and BSDI 3.1 i386.

- Fix `COUNT(*)` problems when the `WHERE` clause didn't match any records. (Bug from 3.21.17.)

- Removed that `NULL = NULL` is true. Now you must use `IS NULL` or `IS NOT NULL` to test whether a value is `NULL`. (This is according to SQL-99 but may break old applications that are ported from `mSQL`.) You can get the old behavior by compiling with `-DmSQL_COMPLIANT`.

- Fixed bug that core dumped when using many `LEFT OUTER JOIN` clauses.

- Fixed bug in `ORDER BY` on string formula with possible `NULL` values.

- Fixed problem in range optimizer when using `<=` on sub index.

- Added functions `DAYOFYEAR()`, `DAYOFMONTH()`, `MONTH()`, `YEAR()`, `WEEK()`, `QUARTER()`, `HOUR()`, `MINUTE()`, `SECOND()` and `FIND_IN_SET()`.

- Added `SHOW VARIABLES` command.

- Added support of ``long constant strings'' from SQL-99:

      mysql> SELECT 'first ' 'second';       -> 'first second'

- Upgraded Msql-Mysql-modules to 1.1825.

- Upgraded `mysqlaccess` to 2.02.

- Fixed problem with Russian character set and `LIKE`.

- Ported to OpenBSD 2.1.

- New Dutch error messages.

### C.6.13. Changements de la version 3.21.21a

- Configure changes for some operating systems.

### C.6.14. Changements de la version 3.21.21

- Fixed optimizer bug when using `WHERE data_field = date_field2 AND date_field2 = constant`.

- Added `SHOW STATUS` command.

- Removed `manual.ps` from the source distribution to make it smaller.

### C.6.15. Changements de la version 3.21.20

- Changed the maximum table name and column name lengths from 32 to 64.

- Aliases can now be of ``any'' length.

- Fixed `mysqladmin stat` to return the right number of queries.

- Changed protocol (downward compatible) to mark if a column has the `AUTO_INCREMENT` attribute or is a `TIMESTAMP`. This is needed for the new Java driver.

- Added Hebrew sorting order by Zeev Suraski.

- Solaris 2.6: Fixed `configure` bugs and increased maximum table size from 2G to 4G.

### C.6.16. Changements de la version 3.21.19

- Upgraded `DBD` to 1.1823. This version implements `mysql_use_result` in `DBD-Mysql`.

- Benchmarks updated for empress (by Luuk).

- Fixed a case of slow range searching.

- Configure fixes (`Docs` directory).

- Added function `REVERSE()` (by Zeev Suraski).

### C.6.17. Changements de la version 3.21.18

- Issue error message if client C functions are called in wrong order.

- Added automatic reconnect to the `libmysql.c` library. If a write command fails, an automatic reconnect is done.

- Small sort sets no longer use temporary files.

- Upgraded `DBI` to 0.91.

- Fixed a couple of problems with `LEFT OUTER JOIN`.

- Added `CROSS JOIN` syntax. `CROSS` is now a reserved word.

- Recoded `yacc`/`bison` stack allocation to be even safer and to allow MySQL to handle even bigger expressions.

- Fixed a couple of problems with the update log.

- `ORDER BY` was slow when used with key ranges.

### C.6.18. Changements de la version 3.21.17

- Changed documentation string of `--with-unix-socket-path` to avoid confusion.

- Added ODBC and SQL-99 style `LEFT OUTER JOIN`.

- The following are new reserved words: `LEFT`, `NATURAL`, `USING`.

- The client library now uses the value of the environment variable `MYSQL_HOST` as the default host if it's defined.

- `SELECT col_name, SUM(expr)` now returns `NULL` for `col_name` when there are matching rows.

- Fixed problem with comparing binary strings and `BLOB` values with ASCII characters over 127.

- Fixed lock problem: when freeing a read lock on a table with multiple read locks, a thread waiting for a write lock would have been given the lock. This shouldn't affect data integrity, but could possibly make `mysqld` restart if one thread was reading data that another thread modified.

- `LIMIT offset,count` didn't work in `INSERT ... SELECT`.

- Optimized key block caching. This will be quicker than the old algorithm when using bigger key caches.

### C.6.19. Changements de la version 3.21.16

- Added ODBC 2.0 & 3.0 functions `POWER()`, `SPACE()`, `COT()`, `DEGREES()`, `RADIANS()`, `ROUND(2 arg)` and `TRUNCATE()`.

- Warning : Incompatible change! `LOCATE()` parameters were swapped according to ODBC standard. Fixed.

- Added function `TIME_TO_SEC()`.

- In some cases, default values were not used for `NOT NULL` fields.

- Timestamp wasn't always updated properly in `UPDATE SET ...` statements.

- Allow empty strings as default values for `BLOB` and `TEXT`, to be compatible with `mysqldump`.

### C.6.20. Changements de la version 3.21.15

- Warning: Incompatible change! `mysqlperl` is now from Msql-Mysql-modules. This means that `connect()` now takes `host`, `database`, `user`, `password` arguments! The old version took `host`, `database`, `password`, `user`.

- Allow `DATE '1997-01-01'`, `TIME '12:10:10'` and `TIMESTAMP '1997-01-01 12:10:10'` formats required by SQL-99. Warning: Incompatible change! This has the unfortunate side-effect that you no longer can have columns named `DATE`, `TIME` or `TIMESTAMP`. :( Old columns can still be accessed through `tablename.columnname`!)

- Changed Makefiles to hopefully work better with BSD systems. Also, `manual.dvi` is now included in the distribution to avoid having stupid `make` programs trying to rebuild it.

- `readline` library upgraded to version 2.1.

- A new sortorder german-1. That is a normal ISO-Latin1 with a german sort order.

- Perl `DBI`/`DBD` is now included in the distribution. `DBI` is now the recommended way to connect to MySQL from Perl.

- New portable benchmark suite with `DBD`, with test results from `mSQL` 2.0.3, MySQL, PostgreSQL 6.2.1 and Solid server 2.2.

- `crash-me` is now included with the benchmarks; this is a Perl program designed to find as many limits as possible in an SQL server. Tested with `mSQL`, PostgreSQL, Solid and MySQL.

- Fixed bug in range-optimizer that crashed MySQL on some queries.

- Table and column name completion for `mysql` command-line tool, by Zeev Suraski and Andi Gutmans.

- Added new command `REPLACE` that works like `INSERT` but replaces conflicting records with the new record. `REPLACE INTO TABLE ... SELECT ...` works also.

- Added new commands `CREATE DATABASE db_name` and `DROP DATABASE db_name`.

- Added `RENAME` option to `ALTER TABLE`: `ALTER TABLE name RENAME TO new_name`.

- `make_binary_distribution` now includes `libgcc.a` in `libmysqlclient.a`. This should make linking work for people who don't have `gcc`.

- Changed `net_write()` to `my_net_write()` because of a name conflict with Sybase.

- New function `DAYOFWEEK()` compatible with ODBC.

- Stack checking and `bison` memory overrun checking to make MySQL safer with weird queries.

### C.6.21. Changements de la version 3.21.14b

- Fixed a couple of small `configure` problems on some platforms.

### C.6.22. Changements de la version 3.21.14a

- Ported to SCO Openserver 5.0.4 with FSU Pthreads.

- HP-UX 10.20 should work.

- Added new function `DATE_FORMAT()`.

- Added `NOT IN`.

- Added automatic removal of 'ODBC function conversions': `{fn now() }`

- Handle ODBC 2.50.3 option flags.

- Fixed comparison of `DATE` and `TIME` values with `NULL`.

- Changed language name from germany to german to be consistent with the other language names.

- Fixed sorting problem on functions returning a `FLOAT`. Previously, the values were converted to `INT` values before sorting.

- Fixed slow sorting when sorting on key field when using `key_column=constant`.

- Sorting on calculated `DOUBLE` values sorted on integer results instead.

- `mysql` no longer requires a database argument.

- Changed the place where `HAVING` should be. According to the SQL standards, it should be after `GROUP BY` but before `ORDER BY`. MySQL Version 3.20 incorrectly had it last.

- Added Sybase command `USE database` to start using another database.

- Added automatic adjusting of number of connections and table cache size if the maximum number of files that can be opened is less than needed. This should fix that `mysqld` doesn't crash even if you haven't done a `ulimit -n 256` before starting `mysqld`.

- Added lots of limit checks to make it safer when running with too little memory or when doing weird queries.

### C.6.23. Changements de la version 3.21.13

- Added retry of interrupted reads and clearing of `errno`. This makes Linux systems much safer!

- Fixed locking bug when using many aliases on the same table in the same `SELECT`.

- Fixed bug with `LIKE` on number key.

- New error message so you can check whether the connection was lost while the command was running or whether the connection was down from the start.

- Added `--table` option to `mysql` to print in table format. Moved time and row information after query result. Added automatic reconnect of lost connections.

- Added `!=` as a synonym for `<>`.

- Added function `VERSION()` to make easier logs.

- New multi-user test `tests/fork_test.pl` to put some strain on the thread library.

### C.6.24. Changements de la version 3.21.12

- Fixed `ftruncate()` call in MIT-pthreads. This made `isamchk` destroy the `.ISM` files on (Free)BSD 2.x systems.

- Fixed broken `__P_` patch in MIT-pthreads.

- Many memory overrun checks. All string functions now return `NULL` if the returned string should be longer than `max_allowed_packet` bytes.

- Changed the name of the `INTERVAL` type to `ENUM`, because `INTERVAL` is used in SQL-99.

- In some cases, doing a `JOIN` + `GROUP` + `INTO OUTFILE`, the result wasn't grouped.

- `LIKE` with `'_'` as last character didn't work. Fixed.

- Added extended SQL-99 `TRIM()` function.

- Added `CURTIME()`.

- Added `ENCRYPT()` function by Zeev Suraski.

- Fixed better `FOREIGN KEY` syntax skipping. New reserved words: `MATCH`, `FULL`, `PARTIAL`.

- `mysqld` now allows IP number and hostname for the `--bind-address` option.

- Added `SET CHARACTER SET cp1251_koi8` to enable conversions of data to and from the `cp1251_koi8` character set.

- Lots of changes for Windows 95 port. In theory, this version should now be easily portable to Windows 95.

- Changed the `CREATE COLUMN` syntax of `NOT NULL` columns to be after the `DEFAULT` value, as specified in the SQL-99 standard. This will make `mysqldump` with `NOT NULL` and default values incompatible with MySQL Version 3.20.

- Added many function name aliases so the functions can be used with ODBC or SQL-92 syntax.

- Fixed syntax of `ALTER TABLE tbl_name ALTER COLUMN col_name SET DEFAULT NULL`.

- Added `CHAR` and `BIT` as synonyms for `CHAR(1)`.

- Fixed core dump when updating as a user who has only `SELECT` privilege.

- `INSERT ... SELECT ... GROUP BY` didn't work in some cases. An `Invalid use of group function` error occurred.

- When using `LIMIT`, `SELECT` now always uses keys instead of record scan. This will give better performance on `SELECT` and a `WHERE` that matches many rows.

- Added Russian error messages.

### C.6.25. Changements de la version 3.21.11

- Configure changes.

- MySQL now works with the new thread library on BSD/OS 3.0.

- Added new group functions `BIT_OR()` and `BIT_AND()`.

- Added compatibility functions `CHECK` and `REFERENCES`. `CHECK` is now a reserved word.

- Added `ALL` option to `GRANT` for better compatibility. (`GRANT` is still a dummy function.)

- Added partly translated Dutch error messages.

- Fixed bug in `ORDER BY` and `GROUP BY` with `NULL` columns.

- Added function `LAST_INSERT_ID()` SQL function to retrieve last `AUTO_INCREMENT` value. This is intended for clients to ODBC that can't use the `mysql_insert_id()` API function, but can be used by any client.

- Added `--flush-logs` option to `mysqladmin`.

- Added command `STATUS` to `mysql`.

- Fixed problem with `ORDER BY`/`GROUP BY` because of bug in `gcc`.

- Fixed problem with `INSERT ... SELECT ... GROUP BY`.

### C.6.26. Changements de la version 3.21.10

- New program `mysqlaccess`.

- `CREATE` now supports all ODBC types and the `mSQL` `TEXT` type. All ODBC 2.5 functions are also supported (added `REPEAT`). This provides better portability.

- Added text types `TINYTEXT`, `TEXT`, `MEDIUMTEXT` and `LONGTEXT`. These are actually `BLOB`types, but all searching is done in case-insensitive fashion.

- All old `BLOB` fields are now `TEXT` fields. This only changes that all searching on strings is done in case-sensitive fashion. You must do an `ALTER TABLE` and change the datatype to `BLOB` if you want to have tests done in case-sensitive fashion.

- Fixed some `configure` issues.

- Made the locking code a bit safer. Fixed very unlikely deadlock situation.

- Fixed a couple of bugs in the range optimizer. Now the new range benchmark `test-select` works.

### C.6.27. Changements de la version 3.21.9

- Added `--enable-unix-socket=pathname` option to `configure`.

- Fixed a couple of portability problems with include files.

- Fixed bug in range calculation that could return empty set when searching on multiple key with only one entry (very rare).

- Most things ported to FSU Pthreads, which should allow MySQL to run on SCO. See Section 2.8.5.8, « Notes sur SCO ».

### C.6.28. Changements de la version 3.21.8

- Works now in Solaris 2.6.

- Added handling of calculation of `SUM()` functions. For example, you can now use `SUM(column)/COUNT(column)`.

- Added handling of trigometric functions: `PI()`, `ACOS()`, `ASIN()`, `ATAN()`, `COS()`, `SIN()` and `TAN()`.

- New languages: Norwegian, Norwegian-ny and Portuguese.

- Fixed parameter bug in `net_print()` in `procedure.cc`.

- Fixed a couple of memory leaks.

- Now allow also the old `SELECT ... INTO OUTFILE` syntax.

- Fixed bug with `GROUP BY` and `SELECT` on key with many values.

- `mysql_fetch_lengths()` sometimes returned incorrect lengths when you used `mysql_use_result()`. This affected at least some cases of `mysqldump --quick`.

- Fixed bug in optimization of `WHERE const op field`.

- Fixed problem when sorting on `NULL` fields.

- Fixed a couple of 64-bit (Alpha) problems.

- Added `--pid-file=#` option to `mysqld`.

- Added date formatting to `FROM_UNIXTIME()`, originally by Zeev Suraski.

- Fixed bug in `BETWEEN` in range optimizer (did only test = of the first argument).

- Added machine-dependent files for MIT-pthreads i386-SCO. There is probably more to do to get this to work on SCO 3.5.

### C.6.29. Changements de la version 3.21.7

- Changed `Makefile.am` to take advantage of Automake 1.2.

- Added the beginnings of a benchmark suite.

- Added more secure password handling.

- Added new client function `mysql_errno()`, to get the error number of the error message. This makes error checking in the client much easier. This makes the new server incompatible with the 3.20.x server when running without `--old-protocol`. The client code is backward-compatible. More information can be found in the `README` file!

- Fixed some problems when using very long, illegal names.

### C.6.30. Changements de la version 3.21.6

- Fixed more portability issues (incorrect `sigwait` and `sigset` defines).

- `configure` should now be able to detect the last argument to `accept()`.

### C.6.31. Changements de la version 3.21.5

- Should now work with FreeBSD 3.0 if used with `FreeBSD-3.0-libc_r-1.0.diff`, which can be found at http://www.mysql.com/downloads/os-freebsd.html.

- Added new `-O tmp_table_size=#` option to `mysqld`.

- New function `FROM_UNIXTIME(timestamp)` which returns a date string in `'YYYY-MM-DD HH:MM:SS'` format.

- New function `SEC_TO_TIME(seconds)` which returns a string in `'HH:MM:SS'` format.

- New function `SUBSTRING_INDEX()`, originally by Zeev Suraski.

### C.6.32. Changements de la version 3.21.4

- Should now configure and compile on OSF/1 4.0 with the DEC compiler.

- Configuration and compilation on BSD/OS 3.0 works, but due to some bugs in BSD/OS 3.0, `mysqld` doesn't work on it yet.

- Configuration and compilation on FreeBSD 3.0 works, but I couldn't get `pthread_create` to work.

### C.6.33. Changements de la version 3.21.3

- Added reverse check lookup of hostnames to get better security.

- Fixed some possible buffer overflows if filenames that are too long are used.

- `mysqld` doesn't accept hostnames that start with digits followed by a `'.'`, because the hostname may look like an IP number.

- Added `--skip-networking` option to `mysqld`, to allow only socket connections. (This will not work with MIT-pthreads!)

- Added check of too long table names for alias.

- Added check if database name is okay.

- Added check if too long table names.

- Removed incorrect `free()` that killed the server on `CREATE DATABASE` or `DROP DATABASE`.

- Changed some `mysqld` `-O` options to better names.

- Added `-O join_cache_size=#` option to `mysqld`.

- Added `-O max_join_size=#` option to `mysqld`, to be able to set a limit how big queries (in this case big = slow) one should be able to handle without specifying `SET SQL_BIG_SELECTS=1`. A # = is about 10 examined records. The default is ``unlimited''.

- When comparing a `TIME`, `DATE`, `DATETIME` or `TIMESTAMP` column to a constant, the constant is converted to a time value before performing the comparison. This will make it easier to get ODBC (particularly Access97) to work with the above types. It should also make dates easier to use and the comparisons should be quicker than before.

- Applied patch from Jochen Wiedmann that allows `query()` in `mysqlperl` to take a query with `\0` in it.

- Storing a timestamp with a 2-digit year (`YYMMDD`) didn't work.

- Fix that timestamp wasn't automatically updated if set in an `UPDATE` clause.

- Now the automatic timestamp field is the FIRST timestamp field.

- `SELECT * INTO OUTFILE`, which didn't correctly if the outfile already existed.

- `mysql` now shows the thread ID when starting or doing a reconnect.

- Changed the default sort buffer size from 2M to 1M.

### C.6.34. Changements de la version 3.21.2

- The range optimizer is coded, but only 85% tested. It can be enabled with `--new`, but it crashes core a lot yet...

- More portable. Should compile on AIX and alpha-digital. At least the `isam` library should be relatively 64-bit clean.

- New `isamchk` which can detect and fix more problems.

- New options for `isamlog`.

- Using new version of Automake.

- Many small portability changes (from the AIX and alpha-digital port) Better checking of pthread(s) library.

- czech error messages by `<snajdr@pvt.net>`.

- Decreased size of some buffers to get fewer problems on systems with little memory. Also added more checks to handle ``out of memory'' problems.

- `mysqladmin`: you can now do `mysqladmin kill 5,6,7,8` to kill multiple threads.

- When the maximum connection limit is reached, one extra connection by a user with the process_acl privilege is granted.

- Added `-O backlog=#` option to `mysqld`.

- Increased maximum packet size from 512K to 1024K for client.

- Almost all of the function code is now tested in the internal test suite.

- `ALTER TABLE` now returns warnings from field conversions.

- Port changed to 3306 (got it reserved from ISI).

- Added a fix for Visual FoxBase so that any schema name from a table specification is automatically removed.

- New function `ASCII()`.

- Removed function `BETWEEN(a,b,c)`. Use the standard SQL syntax instead: `expr BETWEEN expr AND expr`.

- MySQL no longer has to use an extra temporary table when sorting on functions or `SUM()` functions.

- Fixed bug that you couldn't use `tbl_name.field_name` in `UPDATE`.

- Fixed `SELECT DISTINCT` when using 'hidden group'. For example:

      mysql> SELECT DISTINCT MOD(some_field,10) FROM test
          ->        GROUP BY some_field;

  Note: `some_field` is normally in the `SELECT` part. Standard SQL should require it.

### C.6.35. Changements de la version 3.21.0

- New reserved words used: `INTERVAL`, `EXPLAIN`, `READ`, `WRITE`, `BINARY`.

- Added ODBC function `CHAR(num,...)`.

- New operator `IN`. This uses a binary search to find a match.

- New command `LOCK TABLES tbl_name [AS alias] {READ|WRITE} ...`

- Added `--log-update` option to `mysqld`, to get a log suitable for incremental updates.

- New command `EXPLAIN SELECT ...` to get information about how the optimizer will do the join.

- For easier client code, the client should no longer use `FIELD_TYPE_TINY_BLOB`, `FIELD_TYPE_MEDIUM_BLOB`, `FIELD_TYPE_LONG_BLOB` or `FIELD_TYPE_VAR_STRING` (as previously returned by `mysql_list_fields`). You should instead only use `FIELD_TYPE_BLOB` or `FIELD_TYPE_STRING`. If you want exact types, you should use the command `SHOW FIELDS`.

- Added varbinary syntax: `0x######` which can be used as a string (default) or a number.

- `FIELD_TYPE_CHAR` is renamed to `FIELD_TYPE_TINY`.

- Changed all fields to C++ classes.

- Removed FORM struct.

- Fields with `DEFAULT` values no longer need to be `NOT NULL`.

- New field types:

  - `ENUM`

    A string which can take only a couple of defined values. The value is stored as a 1-3 byte number that is mapped automatically to a string. This is sorted according to string positions!

  - `SET`

    A string which may have one or many string values separated with ','. The string is stored as a 1-, 2-, 3-, 4- or 8-byte number where each bit stands for a specific set member. This is sorted according to the unsigned value of the stored packed number.

- Now all function calculation is done with `double` or `long long`. This will provide the full 64-bit range with bit functions and fix some conversions that previously could result in precision losses. One should avoid using `unsigned long long` columns with full 64-bit range (numbers bigger than 9223372036854775807) because calculations are done with `signed long long`.

- `ORDER BY` will now put `NULL` field values first. `GROUP BY` will also work with `NULL` values.

- Full `WHERE` with expressions.

- New range optimizer that can resolve ranges when some keypart prefix is constant. Example:

      mysql> SELECT * FROM tbl_name
          ->          WHERE key_part_1="customer"
          ->          AND key_part_2>=10 AND key_part_2<=10;

## C.7. Changements de la version 3.20.x

La version 3.20 est plutôt vieille, et doit être évitée si possible. Les informations de cette section sont conservées à des fins d'archives.

Les changements des versions 3.20.18 à 3.20.32b ne sont pas documentés ici, car la version 3.21 a commencé ici. Les modifications importantes sont documentés dans l'histoiriqe de la version 3.21.

### C.7.1. Changements de la version 3.20.18

- Added `-p#` (remove `#` directories from path) to `isamlog`. All files are written with a relative path from the database directory Now `mysqld` shouldn't crash on shutdown when using the `--log-isam` option.

- New `mysqlperl` version. It is now compatible with `msqlperl-0.63`.

- New `DBD` module available.

- Added group function `STD()` (standard deviation).

- The `mysqld` server is now compiled by default without debugging information. This will make the daemon smaller and faster.

- Now one usually only has to specify the `--basedir` option to `mysqld`. All other paths are relative in a normal installation.

- `BLOB` columns sometimes contained garbage when used with a `SELECT` on more than one table and `ORDER BY`.

- Fixed that calculations that are not in `GROUP BY` work as expected (SQL-99 extension). Example:

      mysql> SELECT id,id+1 FROM table GROUP BY id;

- The test of using `MYSQL_PWD` was reversed. Now `MYSQL_PWD` is enabled as default in the default release.

- Fixed conversion bug which caused `mysqld` to core dump with Arithmetic error on SPARC-386.

- Added `--unbuffered` option to `mysql`, for new `mysqlaccess`.

- When using overlapping (unnecessary) keys and join over many tables, the optimizer could get confused and return 0 records.

### C.7.2. Changements de la version 3.20.17

- You can now use `BLOB` columns and the functions `IS NULL` and `IS NOT NULL` in the `WHERE` clause.

- All communication packets and row buffers are now allocated dynamically on demand. The default value of `max_allowed_packet` is now 64K for the server and 512K for the client. This is mainly used to catch incorrect packets that could trash all memory. The server limit may be changed when it is started.

- Changed stack usage to use less memory.

- Changed `safe_mysqld` to check for running daemon.

- The `ELT()` function is renamed to `FIELD()`. The new `ELT()` function returns a value based on an index: `FIELD()` is the inverse of `ELT()` Example: `ELT(2,"A","B","C")` returns `"B"`. `FIELD("B","A","B","C")` returns `2`.

- `COUNT(field)`, where `field` could have a `NULL` value, now works.

- A couple of bugs fixed in `SELECT ... GROUP BY`.

- Fixed memory overrun bug in `WHERE` with many unoptimizable brace levels.

- Fixed some small bugs in the grant code.

- If hostname isn't found by `get_hostname`, only the IP is checked. Previously, you got `Access denied`.

- Inserts of timestamps with values didn't always work.

- `INSERT INTO ... SELECT ... WHERE` could give the error `Duplicated field`.

- Added some tests to `safe_mysqld` to make it ``safer''.

- `LIKE` was case-sensitive in some places and case-insensitive in others. Now `LIKE` is always case-insensitive.

- `mysql.cc`: Allow `'#'` anywhere on the line.

- New command `SET SQL_SELECT_LIMIT=#`. See the FAQ for more details.

- New version of the `mysqlaccess` script.

- Change `FROM_DAYS()` and `WEEKDAY()` to also take a full `TIMESTAMP` or `DATETIME` as argument. Before they only took a number of type `YYYYMMDD` or `YYMMDD`.

- Added new function `UNIX_TIMESTAMP(timestamp_column)`.

### C.7.3. Changements de la version 3.20.16

- More changes in MIT-pthreads to get them safer. Fixed also some link bugs at least in SunOS.

- Changed `mysqld` to work around a bug in MIT-pthreads. This makes multiple small `SELECT` operations 20 times faster. Now `lock_test.pl` should work.

- Added `mysql_FetchHash(handle)` to `mysqlperl`.

- The `mysqlbug` script is now distributed built to allow for reporting bugs that appear during the build with it.

- Changed `libmysql.c` to prefer `getpwuid()` instead of `cuserid()`.

- Fixed bug in `SELECT` optimizer when using many tables with the same column used as key to different tables.

- Added new `latin2` and Russian `KOI8` character tables.

- Added support for a dummy `GRANT` command to satisfy Powerbuilder.

### C.7.4. Changements de la version 3.20.15

- Fixed fatal bug `packets out of order` when using MIT-pthreads.

- Removed possible loop when a thread waits for command from client and `fcntl()` fails. Thanks to Mike Bretz for finding this bug.

- Changed alarm loop in `mysqld.cc` because shutdown didn't always succeed in Linux.

- Removed use of `termbits` from `mysql.cc`. This conflicted with `glibc` 2.0.

- Fixed some syntax errors for at least BSD and Linux.

- Fixed bug when doing a `SELECT` as superuser without a database.

- Fixed bug when doing `SELECT` with group calculation to outfile.

### C.7.5. Changements de la version 3.20.14

- If one gives `-p` or `--password` option to `mysql` without an argument, the user is solicited for the password from the tty.

- Added default password from `MYSQL_PWD` (by Elmar Haneke).

- Added command `kill` to `mysqladmin` to kill a specific MySQL thread.

- Sometimes when doing a reconnect on a down connection this succeeded first on second try.

- Fixed adding an `AUTO_INCREMENT` key with `ALTER_TABLE`.

- `AVG()` gave too small value on some `SELECT` statements with `GROUP BY` and `ORDER BY`.

- Added new `DATETIME` type (by Giovanni Maruzzelli `<maruzz@matrice.it>`).

- Fixed that defining `DONT_USE_DEFAULT_FIELDS` works.

- Changed to use a thread to handle alarms instead of signals on Solaris to avoid race conditions.

- Fixed default length of signed numbers. (George Harvey `<georgeh@pinacl.co.uk>`.)

- Allow anything for `CREATE INDEX`.

- Add prezeros when packing numbers to `DATE`, `TIME` and `TIMESTAMP`.

- Fixed a bug in `OR` of multiple tables (gave empty set).

- Added many patches to MIT-pthreads. This fixes at least one lookup bug.

### C.7.6. Changements de la version 3.20.13

- Added standard SQL-92 `DATE` and `TIME` types.

- Fixed bug in `SELECT` with `AND`-`OR` levels.

- Added support for Slovenian characters. The `Contrib` directory contains source and instructions for adding other character sets.

- Fixed bug with `LIMIT` and `ORDER BY`.

- Allow `ORDER BY` and `GROUP BY` on items that aren't in the `SELECT` list. (Thanks to Wim Bonis `<bonis@kiss.de>`, for pointing this out.)

- Allow setting of timestamp values in `INSERT`.

- Fixed bug with `SELECT ... WHERE ... = NULL`.

- Added changes for `glibc` 2.0. To get `glibc` to work, you should add the `gibc-2.0-sigwait-patch` before compiling `glibc`.

- Fixed bug in `ALTER TABLE` when changing a `NOT NULL` field to allow `NULL` values.

- Added some SQL-92 synonyms as field types to `CREATE TABLE`. `CREATE TABLE` now allows `FLOAT(4)` and `FLOAT(8)` to mean `FLOAT` and `DOUBLE`.

- New utility program `mysqlaccess` by `<Yves.Carlier@rug.ac.be>`. This program shows the access rights for a specific user and the grant rows that determine this grant.

- Added `WHERE const op field` (by `<bonis@kiss.de>`).

### C.7.7. Changements de la version 3.20.11

- When using `SELECT ... INTO OUTFILE`, all temporary tables are ISAM instead of HEAP to allow big dumps.

- Changed date functions to be string functions. This fixed some ``funny'' side effects when sorting on dates.

- Extended `ALTER TABLE` for SQL-92 compliance.

- Some minor compatibility changes.

- Added `--port` and `--socket` options to all utility programs and `mysqld`.

- Fixed `MIT-pthreads` `readdir_r()`. Now `mysqladmin create database` and `mysqladmin drop database` should work.

- Changed `MIT-pthreads` to use our `tempnam()`. This should fix the ``sort aborted'' bug.

- Added sync of records count in `sql_update`. This fixed slow updates on first connection. (Thanks to Vaclav Bittner for the test.)

### C.7.8. Changements de la version 3.20.10

- New insert type: `INSERT INTO ... SELECT ...`

- `MEDIUMBLOB` fixed.

- Fixed bug in `ALTER TABLE` and `BLOB` values.

- `SELECT ... INTO OUTFILE` now creates the file in the current database directory.

- `DROP TABLE` now can take a list of tables.

- Oracle synonym `DESCRIBE` (`DESC`).

- Changes to `make_binary_distribution`.

- Added some comments to installation instructions about `configure`'s C++ link test.

- Added `--without-perl` option to `configure`.

- Lots of small portability changes.

### C.7.9. Changements de la version 3.20.9

- `ALTER TABLE` didn't copy null bit. As a result, fields that were allowed to have `NULL` values were always `NULL`.

- `CREATE` didn't take numbers as `DEFAULT`.

- Some compatibility changes for SunOS.

- Removed `config.cache` from old distribution.

### C.7.10. Changements de la version 3.20.8

- Fixed bug with `ALTER TABLE` and multi-part keys.

### C.7.11. Changements de la version 3.20.7

- New commands: `ALTER TABLE`, `SELECT ... INTO OUTFILE` and `LOAD DATA INFILE`.

- New function: `NOW()`.

- Added new field `File_priv` to `mysql/user` table.

- New script `add_file_priv` which adds the new field `File_priv` to the `user` table. This script must be executed if you want to use the new `SELECT ... INTO` and `LOAD DATA INFILE ...` commands with a version of MySQL earlier than 3.20.7.

- Fixed bug in locking code, which made `lock_test.pl` test fail.

- New files `NEW` and `BUGS`.

- Changed `select_test.c` and `insert_test.c` to include `config.h`.

- Added `status` command to `mysqladmin` for short logging.

- Increased maximum number of keys to 16 and maximum number of key parts to 15.

- Use of sub keys. A key may now be a prefix of a string field.

- Added `-k` option to `mysqlshow`, to get key information for a table.

- Added long options to `mysqldump`.

### C.7.12. Changements de la version 3.20.6

- Portable to more systems because of MIT-pthreads, which will be used automatically if `configure` cannot find a `-lpthreads` library.

- Added GNU-style long options to almost all programs. Test with `program --help`.

- Some shared library support for Linux.

- The FAQ is now in `.texi` format and is available in `.html`, `.txt` and `.ps` formats.

- Added new SQL function `RAND([init])`.

- Changed `sql_lex` to handle `\0` unquoted, but the client can't send the query through the C API, because it takes a str pointer. You must use `mysql_real_query()` to send the query.

- Added API function `mysql_get_client_info()`.

- `mysqld` now uses the `N_MAX_KEY_LENGTH` from `nisam.h` as the maximum allowable key length.

- The following now works:

      mysql> SELECT filter_nr,filter_nr FROM filter ORDER BY filter_nr;

  Previously, this resulted in the error: `Column: 'filter_nr' in order clause is ambiguous`.

- `mysql` now outputs `'\0'`, `'\t'`, `'\n'` and `'\\'` when encountering ASCII 0, tab, newline or `'\'` while writing tab-separated output. This is to allow printing of binary data in a portable format. To get the old behavior, use `-r` (or `--raw`).

- Added german error messages (60 of 80 error messages translated).

- Added new API function `mysql_fetch_lengths(MYSQL_RES *)`, which returns an array of column lengths (of type `uint`).

- Fixed bug with `IS NULL` in `WHERE` clause.

- Changed the optimizer a little to get better results when searching on a key part.

- Added `SELECT` option `STRAIGHT_JOIN` to tell the optimizer that it should join tables in the given order.

- Added support for comments starting with `'--'` in `mysql.cc` (Postgres syntax).

- You can have `SELECT` expressions and table columns in a `SELECT` which are not used in the group part. This makes it efficient to implement lookups. The column that is used should be a constant for each group because the value is calculated only once for the first row that is found for a group.

      mysql> SELECT id,lookup.text,SUM(*) FROM test,lookup
          ->        WHERE test.id=lookup.id GROUP BY id;

- Fixed bug in `SUM(function)` (could cause a core dump).

- Changed `AUTO_INCREMENT` placement in the SQL query:

      INSERT INTO table (auto_field) VALUES (0);

  inserted 0, but it should insert an `AUTO_INCREMENT` value.

- `mysqlshow.c`: Added number of records in table. Had to change the client code a little to fix this.

- `mysql` now allows doubled `''` or `""` within strings for embedded `'` or `"`.

- New math functions: `EXP()`, `LOG()`, `SQRT()`, `ROUND()`, `CEILING()`.

### C.7.13. Changements de la version 3.20.3

- The `configure` source now compiles a thread-free client library `-lmysqlclient`. This is the only library that needs to be linked with client applications. When using the binary releases, you must link with `-lmysql -lmysys -ldbug -lmystrings` as before.

- New `readline` library from `bash-2.0`.

- LOTS of small changes to `configure` and makefiles (and related source).

- It should now be possible to compile in another directory using `VPATH`. Tested with GNU Make 3.75.

- `safe_mysqld` and `mysql.server` changed to be more compatible between the source and the binary releases.

- `LIMIT` now takes one or two numeric arguments. If one argument is given, it indicates the maximum number of rows in a result. If two arguments are given, the first argument indicates the offset of the first row to return, the second is the maximum number of rows. With this it's easy to do a poor man's next page/previous page WWW application.

- Changed name of SQL function `FIELDS()` to `ELT()`. Changed SQL function `INTERVALL()` to `INTERVAL()`.

- Made `SHOW COLUMNS` a synonym for `SHOW FIELDS`. Added compatibility syntax `FRIEND KEY` to `CREATE TABLE`. In MySQL, this creates a non-unique key on the given columns.

- Added `CREATE INDEX` and `DROP INDEX` as compatibility functions. In MySQL, `CREATE INDEX` only checks if the index exists and issues an error if it doesn't exist. `DROP INDEX` always succeeds.

- `mysqladmin.c`: added client version to version information.

- Fixed core dump bug in `sql_acl` (core on new connection).

- Removed `host`, `user` and `db` tables from database `test` in the distribution.

- `FIELD_TYPE_CHAR` can now be signed (-128 to 127) or unsigned (0 to 255) Previously, it was always unsigned.

- Bug fixes in `CONCAT()` and `WEEKDAY()`.

- Changed a lot of source to get `mysqld` to be compiled with SunPro compiler.

- SQL functions must now have a `'('` immediately after the function name (no intervening space). For example, `'USER('` is regarded as beginning a function call, and `'USER ('` is regarded as an identifier `USER` followed by a `'('`, not as a function call.

### C.7.14. Changements de la version 3.20.0

- The source distribution is done with `configure` and Automake. It will make porting much easier. The `readline` library is included in the distribution.

- Separate client compilation: the client code should be very easy to compile on systems which don't have threads.

- The old Perl interface code is automatically compiled and installed. Automatic compiling of `DBD` will follow when the new `DBD` code is ported.

- Dynamic language support: `mysqld` can now be started with Swedish or English (default) error messages.

- New functions: `INSERT()`, `RTRIM()`, `LTRIM()` and `FORMAT()`.

- `mysqldump` now works correctly for all field types (even `AUTO_INCREMENT`). The format for `SHOW FIELDS FROM tbl_name` is changed so the `Type` column contains information suitable for `CREATE TABLE`. In previous releases, some `CREATE TABLE` information had to be patched when re-creating tables.

- Some parser bugs from 3.19.5 (`BLOB` and `TIMESTAMP`) are corrected. `TIMESTAMP` now returns different date information depending on its create length.

- Changed parser to allow a database, table or field name to start with a number or `'_'`.

- All old C code from Unireg changed to C++ and cleaned up. This makes the daemon a little smaller and easier to understand.

- A lot of small bug fixes done.

- New `INSTALL` files (not final version) and some information regarding porting.

## C.8. Changements de la version 3.19.x

La version 3.19 est plutôt vieille, et doit être évitée si possible. Les informations de cette section sont conservées à des fins d'archives.

### C.8.1. Changements de la version 3.19.5

- Some new functions, some more optimization on joins.

- Should now compile clean on Linux (2.0.x).

- Added functions `DATABASE()`, `USER()`, `POW()`, `LOG10()` (needed for ODBC).

- In a `WHERE` with an `ORDER BY` on fields from only one table, the table is now preferred as first table in a multi-join.

- `HAVING` and `IS NULL` or `IS NOT NULL` now works.

- A group on one column and a sort on a group function (`SUM()`, `AVG()`...) didn't work together. Fixed.

- `mysqldump`: Didn't send password to server.

### C.8.2. Changements de la version 3.19.4

- Fixed horrible locking bug when inserting in one thread and reading in another thread.

- Fixed one-off decimal bug. 1.00 was output as 1.0.

- Added attribute `'Locked'` to process list as information if a query is locked by another query.

- Fixed full magic timestamp. Timestamp length may now be 14, 12, 10, 8, 6, 4 or 2 bytes.

- Sort on some numeric functions could sort incorrectly on last number.

- `IF(arg,syntax_error,syntax_error)` crashed.

- Added functions `CEILING()`, `ROUND()`, `EXP()`, `LOG()` and `SQRT()`.

- Enhanced `BETWEEN` to handle strings.

### C.8.3. Changements de la version 3.19.3

- Fixed `SELECT` with grouping on `BLOB` columns not to return incorrect `BLOB` info. Grouping, sorting and distinct on `BLOB` columns will not yet work as expected (probably it will group/sort by the first 7 characters in the `BLOB`). Grouping on formulas with a fixed string size (use `MID()` on a `BLOB`) should work.

- When doing a full join (no direct keys) on multiple tables with `BLOB` fields, the `BLOB` was garbage on output.

- Fixed `DISTINCT` with calculated columns.

## C.9. Evolutions de InnoDB

Depuis les versions 4.0.22 et 4.1.5, toutes les évolutions de `InnoDB` sont incluses dans l'historique de MySQL, et cette section ne sera plus gérée indépendamment.

Note : cette section n'est pas traduite en fran¸ais.

### C.9.1. MySQL/InnoDB-4.0.21, pas publiée

Fonctionnalité ajoutée ou modifiée :

Bogues corrigés :

- If you configure `innodb_additional_mem_pool_size` so small that InnoDB memory allocation spills over from it, then every 4 billionth spill may cause memory corruption. A symptom is a printout like below in the `.err` log. The workaround is to make `innodb_additional_mem_pool_size` big enough to hold all memory allocation. Use `SHOW INNODB STATUS` to determine that there is plenty of free space available in the additional mem pool, and the total allocated memory stays rather constant.

      InnoDB: Error: Mem area size is 0. Possibly a memory overrun of the
      InnoDB: previous allocated area!
      InnoDB: Apparent memory corruption: mem dump  len 500; hex

### C.9.2. MySQL/InnoDB-4.1.4, 31 Août 2004

Fonctionnalité ajoutée ou modifiée :

- Important: Made internal representation of `TIMESTAMP` values in `InnoDB` in 4.1 to be the same as in 4.0. This difference resulted in incorrect datetime values in `TIMESTAMP` columns in `InnoDB` tables after an upgrade from 4.0 to 4.1. (Bug#4492) Warning: extra steps during upgrade required! This means that if you are upgrading from 4.1.x, where x <= 3, to 4.1.4 you should use `mysqldump` for saving and then restoring your `InnoDB` tables with `TIMESTAMP` columns. No conversion is needed if you upgrade from 3.23 or 4.0 to 4.1.4 or later.

- Added a new startup option `innodb_locks_unsafe_for_binlog`. This option forces `InnoDB` not to use next-key locking in searches and index scans.

- Added `innodb_status_file` system variable to mysqld to control whether output from `SHOW INNODB STATUS` is written to a `innodb_status.`<pid>`` file in the data directory. By default, the file is not created. To create it, start mysqld with the `--innodb_status_file=1` option.

- Changes for NetWare to exit InnoDB gracefully on NetWare even in a case of an assertion failure, instead of intentionally crashing the mysqld server process.

Bogues corrigés :

- Fixed a bug in `ON DELETE CASCADE` and `ON UPDATE CASCADE` foreign key constraints: long chains of cascaded operations would cause a stack overflow and crash the server. Cascaded operations are now limited to 15 levels. (Bug#4446)

- Increment the InnoDB watchdog timeout during `CHECK TABLE`. (Bug#2694)

- If you configure `innodb_additional_mem_pool_size` so small that InnoDB memory allocation spills over from it, then every 4 billionth spill may cause memory corruption. A symptom is a printout like below in the `.err` log.

      InnoDB: Error: Mem area size is 0. Possibly a memory overrun of the
      InnoDB: previous allocated area!
      InnoDB: Apparent memory corruption: mem dump  len 500; hex

- Fixed a glitch introduced in 4.0.18 and 4.1.2: in `SHOW TABLE STATUS` InnoDB systematically overestimated the row count by 1 if the table fit on a single 16 kB data page.

- InnoDB created temporary files with the C library function `tmpfile()`. On Windows, the files would be created in the root directory of the current file system. To correct this behavior, the invocations of `tmpfile()` were replaced with code that uses the function `create_temp_file()` in the MySQL portability layer. (Bug#3998)

- If we `RENAME`d a table, InnoDB forgot to load the foreign key constraints that reference the new table name, and forgot to check that they are compatible with the table.

- If there was little file I/O in InnoDB, but the insert buffer was used, it could happen that 'Pending normal aio reads' was bigger than 0, but the I/O handler thread did not get waken up in 600 seconds. This resulted in a hang, and an intentional crashing of mysqld.

### C.9.3. MySQL/InnoDB-4.1.3, 28 Juin 2004

Fonctionnalité ajoutée ou modifiée :

- Important: Starting from MySQL 4.1.3, `InnoDB` uses the same character set comparison functions as MySQL for non-`latin1_swedish_ci` character strings that are not `BINARY`. This changes the sorting order of space and characters < ASCII(32) in those character sets. For `latin1_swedish_ci` character strings and `BINARY` strings, `InnoDB` uses its own pad-spaces-at-end comparison method, which stays unchanged. If you have an `InnoDB` table created with MySQL 4.1.2 or earlier, with an index on a non-`latin1` character set (in the case of 4.1.0 and 4.1.1 with any character set) `CHAR`/`VARCHAR`/or `TEXT` column that is not `BINARY` but may contain characters < ASCII(32), then you should do `ALTER TABLE` or `OPTIMIZE` table on it to regenerate the index, after upgrading to MySQL 4.1.3 or later.

- `OPTIMIZE TABLE` for `InnoDB` tables is now mapped to `ALTER TABLE` rather than to `ANALYZE TABLE`.

- Added an interface for storing the binlog offset in the InnoDB log and flushing the log.

Bogues corrigés :

- The critical bug in 4.1.2 (crash recovery skipping all `.ibd` files if you specify `innodb_file_per_table` on Unix) has been fixed. The bug was a combination of two bugs. Crash recovery ignored the files, because the attempt to lock them in the wrong mode failed. From now on, locks will only be obtained for regular files opened in read/write mode, and crash recovery will stop if an `.ibd` file for a table exists in a database directory but is unaccessible.

- Do not remember the original `select_lock_type` inside `LOCK TABLES`. (Bug#4047)

- The special meaning of the table names `innodb_monitor`, `innodb_lock_monitor`, `innodb_tablespace_monitor`, `innodb_table_monitor`, and `innodb_validate` in `CREATE TABLE` and `DROP TABLE` statements was accidentally removed in MySQL/InnoDB-4.1.2. The diagnostic functions attached to these special table names (see Section 15.12.1, « Le moniteur `InnoDB` ») are accessible again in MySQL/InnoDB-4.1.3.

- When the private SQL parser of InnoDB was modified in MySQL/InnoDB-4.0.19 in order to allow the use of the apostrophe (‘`'`’) in table and column names, the fix relied on a previously unused function `mem_realloc()`, whose implementation was incorrect. As a result, InnoDB can incorrectly parse column and table names as the empty string. The InnoDB `realloc()` implementation has been corrected in MySQL/InnoDB-4.1.3.

- In a clean-up of MySQL/InnoDB-4.1.2, the code for invalidating the query cache was broken. Now the query cache should be correctly invalidated for tables affected by `ON UPDATE CASCADE` or `ON DELETE CASCADE` constraints.

- Fixed a bug : in `LIKE 'abc%'`, the `'%'` did not match the empty string if the character set was not `latin1_swedish_ci`. This bug was fixed by changing the sorting order in these character sets. See the above note about data conversion in 4.1.3.

### C.9.4. MySQL/InnoDB-4.1.2, pas publiée

Fonctionnalité ajoutée ou modifiée :

- Do not assert in `log0log.c`, line 856 if `ib_logfiles` are too small for `innodb_thread_concurrency`. Instead, print instructions how to adjust `my.cnf` and call `exit(1)`.

- If MySQL tries to `SELECT` from an InnoDB table without setting any table locks, print a descriptive error message and assert; some subquery bugs were of this type.

- Added a missing space to the output format of `SHOW INNODB STATUS`; reported by Jocelyn Fournier.

- Support multiple character sets. Note that tables created in other collations than `latin1_swedish_ci` cannot be accessed in MySQL/InnoDB 4.0.

- Allow a key path length in InnoDB to be up to 3,500 bytes; this is needed so that one can create an index on a column with 255 UTF-8 characters.

Bogues corrigés :

- Improved portability to 64-bit platforms, especially Win64.

- Fixed an assertion failure when a purge of a table was not possible because of missing `.ibd` file.

- Fixed a bug : do not retrieve all columns in a table if we only need the 'ref' of the row (usually, the `PRIMARY KEY`) to calculate an `ORDER BY`. (Bug#1942)

- On Unix-like systems, obtain an exclusive advisory lock on InnoDB files, to prevent corruption when multiple instances of MySQL are running on the same set of data files. The Windows version of InnoDB already took a mandatory lock on the files. (Bug#3608)

- All bugfixes from InnoDB-4.0.17, InnoDB-4.0.18, InnoDB-4.0.19 and InnoDB-4.0.20.

### C.9.5. MySQL/InnoDB-4.0.20, 18 mai 2004

Bogues corrigés :

- Make `LOCK TABLE` aware of InnoDB row-level locks. (Bug#3299)

- Fixed race conditions in SHOW INNODB STATUS. (Bug#3596)

### C.9.6. MySQL/InnoDB-4.0.19, 4 mai 2004

Fonctionnalit ajoute ou modifie :

- Better error message when the server has to crash because the buffer pool is exhausted by the lock table or the adaptive hash index.

- Print always the count of pending `pread()` and `pwrite()` calls if there is a long semaphore wait.

- Improve space utilization when rows of 1,500 to 8,000 bytes are inserted in the order of the primary key.

- Remove potential buffer overflow errors by sending diagnostic output to stderr or files instead of stdout or fixed-size memory buffers. As a side effect, the output of `SHOW INNODB STATUS` will be written to a file ``<datadir>`/innodb.status.`<pid>`` every 15 seconds.

Bogues corrigs :

- Fixed a bug : `DROP DATABASE` did not work if `FOREIGN KEY` references were defined within the database. (Bug#3058)

- Remove unnecessary files, functions and variables. Many of these were needed in the standalone version of InnoDB. Remove debug functions and variables from non-debug build.

- Add diagnostic code to analyze an assertion failure in ha_innodb.cc on line 2020 reported by a user. (Bug#2903)

- Fixed a bug : in a `FOREIGN KEY`, `ON UPDATE CASCADE` was not triggered if the update changed a string to another value identical in alphabetical ordering, e.g., ‘`abc`’ -> ‘`aBc`’.

- Protect the reading of the latest foreign key error explanation buffer with a mutex; in theory, a race condition could cause `SHOW INNODB STATUS` print garbage characters after the error info.

- Fixed a bug : The row count and key cardinality estimate was grossly too small if each clustered index page only contained one record.

- Parse `CONSTRAINT FOREIGN KEY` correctly. (Bug#3332)

- Fixed a memory corruption bug on Windows. The bug is present in all InnoDB versions in Windows, but it depends on how the linker places a static array in `srv0srv.c`, whether the bug shows itself. 4 bytes were overwritten with a pointer to a statically allocated string '`get windows aio return value`'.

- Fix a glitch reported by Philippe Lewicki on the general mailing list: do not print a warning to the `.err` log if `read_key` fails with a lock wait timeout error 146.

- Allow quotes to be embedded in strings in the private SQL parser of InnoDB, so that ‘`'`’ can be used in InnoDB table and column names. Display quotes within identifiers properly.

- Debugging: Allow `UNIV_SYNC_DEBUG` to be disabled while `UNIV_DEBUG` is enabled.

- Debugging: Handle magic numbers in a more consistent way.

### C.9.7. MySQL/InnoDB-4.0.18, 13 février 2004

- Do not allow dropping a table referenced by a `FOREIGN KEY` constraint, unless the user does `SET FOREIGN_KEY_CHECKS=0`. The error message here is somewhat misleading ``Cannot delete or update a parent row...'', and must be changed in a future version 4.1.x.

- Make `InnoDB` to remember the `CONSTRAINT` name given by a user for a `FOREIGN KEY`.

- Change the print format of `FOREIGN KEY` constraints spanning multiple databases to ``db_name`.`tbl_name``. But when parsing them, we must also accept ``db_name.tbl_name``, because that was the output format in < 4.0.18.

- An optimization in locking: If `AUTOCOMMIT=1`, then we do not need to make a plain `SELECT` set shared locks even on the `SERIALIZABLE` isolation level, because we know that the transaction is read-only. A read-only transaction can always be performed on the `REPEATABLE READ` level, and that does not endanger the serializability.

- Implement an automatic downgrade from >= 4.1.1 -> 4.0.18 if the user has not created tables in `.ibd` files or used other 4.1.x features. Consult the manual section on multiple tablespaces carefully if you want to downgrade!

- Fixed a bug : MySQL should not allow `REPLACE` to internally perform an `UPDATE` if the table is referenced by a `FOREIGN KEY`. The MySQL manual states that `REPLACE` must resolve a duplicate-key error semantically with `DELETE`(s) + `INSERT`, and not by an `UPDATE`. In versions < 4.0.18 and < 4.1.2, MySQL could resolve a duplicate key conflict in `REPLACE` by doing an `UPDATE` on the existing row, and `FOREIGN KEY` checks could behave in a semantically wrong way. (Bug#2418)

- Fixed a bug : generate `FOREIGN KEY` constraint identifiers locally for each table, in the form `db_name/tbl_name_ibfk_number`. If the user gives the constraint name explicitly, then remember it. These changes should ensure that foreign key id's in a slave are the same as in the master, and `DROP FOREIGN KEY` does not break replication. (Bug#2167)

- Fixed a bug : allow quoting of identifiers in InnoDB's `FOREIGN KEY` definitions with a backtick (`) and a double quote ("). You can now use also spaces in table and column names, if you quote the identifiers. (Bug#1725, Bug#2424)

- Fixed a bug : `FOREIGN KEY ... ON UPDATE/DELETE NO ACTION` must check the foreign key constraint, not ignore it. Since we do not have deferred constraints in `InnoDB`, this bugfix makes `InnoDB` to check `NO ACTION` constraints immediately, like it checks `RESTRICT` constraints.

- Fixed a bug : `InnoDB` crashed in `RENAME TABLE` if `'db_name.tbl_name'` is shorter than 5 characters. (Bug#2689)

- Fixed a bug : in `SHOW TABLE STATUS`, `InnoDB` row count and index cardinality estimates wrapped around at 512 million in 32-bit computers. Note that unless MySQL is compiled with the `BIG_TABLES` option, they will still wrap around at 4 billion.

- Fixed a bug : If there was a `UNIQUE` secondary index, and `NULL` values in that unique index, then with the `IS NULL` predicate, `InnoDB` returned only the first matching row, though there can be many. This bug was introduced in 4.0.16. (Bug#2483)

### C.9.8. MySQL/InnoDB-5.0.0, 24 décembre 2003

- IMPORTANT NOTE: if you upgrade to InnoDB-4.1.1 or higher, you cannot downgrade to a version lower than 4.1.1 any more! That is because earlier versions of InnoDB are not aware of multiple tablespaces.

- InnoDB in 5.0.0 is essentially the same as InnoDB-4.1.1 with the bug fixes of InnoDB-4.0.17 included.

### C.9.9. MySQL/InnoDB-4.0.17, 17 décembre 2003

- Fixed a bug : if you created a column prefix secondary index and updated it so that the last characters in the column prefix were spaces, InnoDB would assert in `row0upd.c`, line 713. The same assertion failed if you updated a column in an ordinary secondary index so that the new value was alphabetically equivalent, but had a different length. This could happen, for example, in the utf-8 character set if you updated a letter to its accented or umlaut form.

- Fixed a bug : InnoDB could think that a secondary index record was not locked though it had been updated to an alphabetically equivalent value, e.g., 'abc' -> 'aBc'.

- Fixed a bug : if you updated a secondary index column to an alphabetically equivalent value, and rolled back your update, InnoDB failed to restore the field in the secondary index to its original value.

- There are still several outstanding non-critical bugs reported in the MySQL bugs database. Their fixing has been delayed, because resources were allocated to the 4.1.1 release.

### C.9.10. MySQL/InnoDB-4.1.1, 4 décembre 2003

- IMPORTANT NOTE: if you upgrade to InnoDB-4.1.1 or higher, you cannot downgrade to a version lower than 4.1.1 any more! That is because earlier versions of InnoDB are not aware of multiple tablespaces.

- Multiple tablespaces now available for InnoDB. You can store each InnoDB type table and its indexes into a separate `.ibd` file into a MySQL database directory, into the same directory where the `.frm` file is stored.

- The MySQL query cache now works for InnoDB tables also if `AUTOCOMMIT=0`, or the statements are enclosed inside `BEGIN ... COMMIT`.

- Reduced InnoDB memory consumption by a few megabytes if one sets the buffer pool size < 8 MB.

- You can use raw disk partitions also in Windows.

### C.9.11. MySQL/InnoDB-4.0.16, 22 octobre 2003

- Fixed a bug : in contrary to what was said in the manual, in a locking read InnoDB set two record locks if a unique exact match search condition was used on a multi-column unique key. For a single column unique key it worked right.

- Fixed a bug : if one used the rename trick `#sql... -> rsql...` to recover a temporary table, InnoDB asserted in `row_mysql_lock_data_dictionary()`.

- There are several outstanding non-critical bugs reported in the MySQL bugs database. Their fixing has been delayed, because resources are allocated to the upcoming 4.1.1 release.

### C.9.12. MySQL/InnoDB-3.23.58, 15 septembre 2003

- Fixed a bug : `InnoDB` could make the index page directory corrupt in the first `B-tree` page splits after `mysqld` startup. A symptom would be an assertion failure in `page0page.c`, in function `page_dir_find_slot()`.

- Fixed a bug : `InnoDB` could in rare cases return an extraneous row if a rollback, purge, and a `SELECT` coincided.

- Fixed a possible hang over the `btr0sea.c` latch if `SELECT` was used inside `LOCK TABLES`.

- Fixed a bug : If a single `DELETE` statement first managed to delete some rows and then failed in a `FOREIGN KEY` error or a `Table is full` error, MySQL did not roll back the whole SQL statement as it should.

### C.9.13. MySQL/InnoDB-4.0.15, 10 septembre 2003

- Fixed a bug : if you updated a row so that the 8000 byte maximum length (without `BLOB` and `TEXT`) was exceeded, InnoDB simply removed the record from the clustered index. In a similar insert, InnoDB would leak reserved file space extents, which would only be freed at the next mysqld startup.

- Fixed a bug : if you used big `BLOB` values, and your log files were relatively small, InnoDB could in a big `BLOB` operation temporarily write over the log produced after the latest checkpoint. If InnoDB would crash at that moment, then the crash recovery would fail, because InnoDB would not be able to scan the log even up to the latest checkpoint. Starting from this version, InnoDB tries to ensure the latest checkpoint is young enough. If that is not possible, InnoDB prints a warning to the `.err` log of MySQL and advises you to make the log files bigger.

- Fixed a bug : setting `innodb_fast_shutdown=0` had no effect.

- Fixed a bug introduced in 4.0.13: if a `CREATE TABLE` ended in a comment, that could cause a memory overrun.

- Fixed a bug : If InnoDB printed `Operating system error number .. in a file operation` to the `.err` log in Windows, the error number explanation was wrong. Workaround: look at section 13.2 of http://www.innodb.com/ibman.php about Windows error numbers.

- Fixed a bug : If you created a column prefix `PRIMARY KEY` like in `t(a CHAR(200), PRIMARY KEY (a(10)))` on a fixed-length `CHAR` column, InnoDB would crash even in a simple `SELECT`. C`CHECK TABLE` would report the table as corrupt, also in the case where the created key was not `PRIMARY`.

### C.9.14. MySQL/InnoDB-4.0.14, 22 juillet 2003

- InnoDB now supports the `SAVEPOINT` and `ROLLBACK TO SAVEPOINT` SQL statements. See http://www.innodb.com/ibman.php#Savepoints for the syntax.

- You can now create column prefix keys like in `CREATE TABLE t (a BLOB, INDEX (a(10)))`.

- You can also use `O_DIRECT` as the `innodb_flush_method` on the latest versions of Linux and FreeBSD. Beware of possible bugs in those operating systems, though.

- Fixed the checksum calculation of data pages. Previously most OS file system corruption went unnoticed. Note that if you downgrade from version >= 4.0.14 to an earlier version < 4.0.14 then in the first startup(s) InnoDB will print warnings:

      InnoDB: Warning: an inconsistent page in the doublewrite buffer
      InnoDB: space id 2552202359 page number 8245, 127'th page in dblwr buf.

  but that is not dangerous and can be ignored.

- Modified the buffer pool replacement algorithm so that it tries to flush modified pages if there are no replaceable pages in the last 10 % of the LRU list. This can reduce disk i/o if the workload is a mixture of reads and writes.

- The buffer pool checkpoint flush algorithm now tries to flush also close neighbors of the page at the end of the flush list. This can speed up database shutdown, and can also speed up disk writes if InnoDB log files are very small compared to the buffer pool size.

- In 4.0.13 we made `SHOW INNODB STATUS` to print detailed info on the latest `UNIQUE KEY` error, but storing that info could slow down `REPLACE` significantly. We no longer store or print the info.

- Fixed a bug : `SET FOREIGN_KEY_CHECKS=0` was not replicated properly in the MySQL replication. The fix will not be backported to 3.23.

- Fixed a bug : the parameter `innodb_max_dirty_pages_pct` forgot to take into account the free pages in the buffer pool. This could lead to excessive flushing even though there were lots of free pages in the buffer pool. Workaround: `SET GLOBAL innodb_max_dirty_pages_pct = 100`.

- Fixed a bug : if there were big index scans then a file read request could starve and InnoDB could assert because of a very long semaphore wait.

- Fixed a bug : if `AUTOCOMMIT=1` then inside `LOCK TABLES` MySQL failed to do the commit after an updating SQL statement if binlogging was not on, and for `SELECT` statements did not commit regardless of binlogging state.

- Fixed a bug : InnoDB could make the index page directory corrupt in the first `B-tree` page splits after a mysqld startup. A symptom would be an assertion in page0page.c, in function page_dir_find_slot().

- Fixed a bug : if in a `FOREIGN KEY` with an `UPDATE CASCADE` clause the parent column was of a different internal storage length than the child column, then a cascaded update would make the column length wrong in the child table and corrupt the child table. Because of MySQL's 'silent column specification changes' a fixed-length `CHAR` column can change internally to a `VARCHAR` and cause this error.

- Fixed a bug : if a non-`latin1` character set was used and if in a `FOREIGN KEY` the parent column was of a different internal storage length than the child column, then all inserts to the child table would fail in a foreign key error.

- Fixed a bug : InnoDB could complain that it cannot find the clustered index record, or in rare cases return an extraneous row if a rollback, purge, and a `SELECT` coincided.

- Fixed a possible hang over the btr0sea.c latch if `SELECT` was used inside `LOCK TABLES`.

- Fixed a bug : contrary to what the release note of 4.0.13 said, the group commit still did not work if the MySQL binlogging was on.

- Fixed a bug : os_event_wait() did not work properly in Unix, which might have caused starvation in various log operations.

- Fixed a bug : if a single `DELETE` statement first managed to delete some rows and then failed in a `FOREIGN KEY` error or a 'Table is full error', MySQL did not roll back the whole SQL statement as it should, and also wrote the failed statement to the binlog, reporting there a non-zero error_code.

- Fixed a bug : the maximum allowed number of columns in a table is 1000, but InnoDB did not check that limit in `CREATE TABLE`, and a subsequent `INSERT` or `SELECT` from that table could cause an assertion.

### C.9.15. MySQL/InnoDB-3.23.57, 20 juin 2003

- Changed the default value of `innodb_flush_log_at_trx_commit` from 0 to 1. If you have not specified it explicitly in your `my.cnf`, and your application runs much slower with this new release, it is because the value 1 causes a log flush to disk at each transaction commit.

- Fixed a bug : InnoDB forgot to call pthread_mutex_destroy() when a table was dropped. That could cause memory leakage on FreeBSD and other non-Linux Unixes.

- Fixed a bug : MySQL could erroneously return 'Empty set' if InnoDB estimated an index range size to 0 records though the range was not empty; MySQL also failed to do the next-key locking in the case of an empty index range.

- Fixed a bug : `GROUP BY` and `DISTINCT` could treat NULL values inequal.

### C.9.16. MySQL/InnoDB-4.0.13, 20 mai 2003

- `InnoDB` now supports `ALTER TABLE DROP FOREIGN KEY`. You have to use `SHOW CREATE TABLE` to find the internally generated foreign key ID when you want to drop a foreign key.

- `SHOW INNODB STATUS` now prints detailed information of the latest detected `FOREIGN KEY` and `UNIQUE KEY` errors. If you do not understand why `InnoDB` gives the error 150 from a `CREATE TABLE`, you can use this statement to study the reason.

- `ANALYZE TABLE` now works also for `InnoDB` type tables. It makes 10 random dives to each of the index trees and updates index cardinality estimates accordingly. Note that since it is only an estimate, repeated runs of `ANALYZE TABLE` may produce different numbers. MySQL uses index cardinality estimates only in join optimization. If some join is not optimized in the right way, you may try using `ANALYZE TABLE`.

- `InnoDB` group commit capability now works also when MySQL binlogging is switched on. There have to be > 2 client threads for the group commit to become active.

- Changed the default value of `innodb_flush_log_at_trx_commit` from 0 to 1. If you have not specified it explicitly in your `my.cnf`, and your application runs much slower with this new release, it is because the value 1 causes a log flush to disk at each transaction commit.

- Added a new global settable MySQL system variable `innodb_max_dirty_pages_pct`. It is an integer in the range 0 - 100. The default is 90. The main thread in `InnoDB` tries to flush pages from the buffer pool so that at most this many percents are not yet flushed at any time.

- If `innodb_force_recovery=6`, do not let `InnoDB` do repair of corrupt pages based on the doublewrite buffer.

- `InnoDB` start-up now happens faster because it does not set the memory in the buffer pool to zero.

- Fixed a bug : The `InnoDB` parser for `FOREIGN KEY` definitions was confused by the keywords 'foreign key' inside MySQL comments.

- Fixed a bug : If you dropped a table to which there was a `FOREIGN KEY` reference, and later created the same table with non-matching column types, `InnoDB` could assert in `dict0load.c`, in function `dict_load_table()`.

- Fixed a bug : `GROUP BY` and `DISTINCT` could treat `NULL` values as not equal. MySQL also failed to do the next-key locking in the case of an empty index range.

- Fixed a bug : Do not commit the current transaction when a MyISAM table is updated; this also makes `CREATE TABLE` not to commit an `InnoDB` transaction, even when binlogging is enabled.

- Fixed a bug : We did not allow `ON DELETE SET NULL` to modify the same table where the delete was made; we can allow it because that cannot produce infinite loops in cascaded operations.

- Fixed a bug : Allow `HANDLER PREV` and `NEXT` also after positioning the cursor with a unique search on the primary key.

- Fixed a bug : If `MIN()` or `MAX()` resulted in a deadlock or a lock wait timeout, MySQL did not return an error, but returned `NULL` as the function value.

- Fixed a bug : `InnoDB` forgot to call `pthread_mutex_destroy()` when a table was dropped. That could cause memory leakage on FreeBSD and other non-Linux Unix systems.

### C.9.17. MySQL/InnoDB-4.1.0, 3 avril 2003

- `InnoDB` now supports up to 64 GB of buffer pool memory in a Windows 32-bit Intel computer. This is possible because `InnoDB` can use the AWE extension of Windows to address memory over the 4 GB limit of a 32-bit process. A new startup variable `innodb_buffer_pool_awe_mem_mb` enables AWE and sets the size of the buffer pool in megabytes.

- Reduced the size of buffer headers and the lock table. `InnoDB` uses 2 % less memory.

### C.9.18. MySQL/InnoDB-3.23.56, 17 mars 2003

- Fixed a major bug in InnoDB query optimization: queries of type SELECT ... WHERE indexcolumn < x and SELECT ... WHERE indexcolumn > x could cause a table scan even if the selectivity would have been very good.

- Fixed a potential bug if MySQL calls store_lock with TL_IGNORE in the middle of a query.

### C.9.19. MySQL/InnoDB-4.0.12, 18 mars 2003

- In crash recovery InnoDB now prints the progress in percents of a transaction rollback.

- Fixed a bug/feature: if your application program used mysql_use_result(), and used >= 2 connections to send SQL queries, it could deadlock on the adaptive hash S-latch in btr0sea.c. Now mysqld releases the S-latch whenever it passes data from a SELECT to the client.

- Fixed a bug : MySQL could erroneously return 'Empty set' if InnoDB estimated an index range size to 0 records though the range was not empty; MySQL also failed to do the next-key locking in the case of an empty index range.

### C.9.20. MySQL/InnoDB-4.0.11, 25 février 2003

- Fixed a bug introduced in 4.0.10: SELECT ... FROM ... ORDER BY ... DESC could hang in an infinite loop.

- An outstanding bug: SET FOREIGN_KEY_CHECKS=0 is not replicated properly in the MySQL replication.

### C.9.21. MySQL/InnoDB-4.0.10, 4 février 2003

- In INSERT INTO t1 SELECT ... FROM t2 WHERE ... MySQL previously set a table level read lock on t2. This lock is now removed.

- Increased SHOW INNODB STATUS max printed length to 200 KB.

- Fixed a major bug in InnoDB query optimization: queries of type SELECT ... WHERE indexcolumn < x and SELECT ... WHERE indexcolumn > x could cause a table scan even if the selectivity would have been very good.

- Fixed a bug : purge could cause a hang in a BLOB table where the primary key index tree was of height 1. Symptom: semaphore waits caused by an X-latch set in btr_free_externally_stored_field().

- Fixed a bug : using InnoDB HANDLER commands on a fresh handle crashed mysqld in ha_innobase::change_active_index().

- Fixed a bug : if MySQL estimated a query in the middle of a SELECT statement, InnoDB could hang on the adaptive hash index latch in btr0sea.c.

- Fixed a bug : InnoDB could report table corruption and assert in page_dir_find_owner_slot() if an adaptive hash index search coincided with purge or an insert.

- Fixed a bug : some file system snapshot tool in Windows 2000 could cause an InnoDB file write to fail with error 33 ERROR_LOCK_VIOLATION. In synchronous writes InnoDB now retries the write 100 times at 1 second intervals.

- Fixed a bug : REPLACE INTO t1 SELECT ... did not work if t1 has an auto-inc column.

- An outstanding bug: SET FOREIGN_KEY_CHECKS=0 is not replicated properly in the MySQL replication.

### C.9.22. MySQL/InnoDB-3.23.55, 24 janvier 2003

- In INSERT INTO t1 SELECT ... FROM t2 WHERE ... MySQL previously set a table level read lock on t2. This lock is now removed.

- Fixed a bug : if the combined size of InnoDB log files was >= 2 GB in a 32-bit computer, InnoDB would write log in a wrong position. That could make crash recovery and InnoDB Hot Backup to fail in log scan.

- Fixed a bug : index cursor restoration could theoretically fail.

- Fixed a bug : an assertion in btr0sea.c, in function btr_search_info_update_slow could theoretically fail in a race of 3 threads.

- Fixed a bug : purge could cause a hang in a BLOB table where the primary key index tree was of height 1. Symptom: semaphore waits caused by an X-latch set in btr_free_externally_stored_field().

- Fixed a bug : if MySQL estimated a query in the middle of a SELECT statement, InnoDB could hang on the adaptive hash index latch in btr0sea.c.

- Fixed a bug : InnoDB could report table corruption and assert in page_dir_find_owner_slot() if an adaptive hash index search coincided with purge or an insert.

- Fixed a bug : some file system snapshot tool in Windows 2000 could cause an InnoDB file write to fail with error 33 ERROR_LOCK_VIOLATION. In synchronous writes InnoDB now retries the write 100 times at 1 second intervals.

- An outstanding bug: SET FOREIGN_KEY_CHECKS=0 is not replicated properly in the MySQL replication. The fix will appear in 4.0.11 and will probably not be backported to 3.23.

- Fixed bug in `InnoDB` `page0cur.c` file in function page_cur_search_with_match which caused `InnoDB` to remain on the same page forever. This bug is evident only in tables with more than one page.

### C.9.23. MySQL/InnoDB-4.0.9, 14 janvier 2003

- Removed the warning message: 'InnoDB: Out of memory in additional memory pool.'

- Fixed a bug : if the combined size of InnoDB log files was >= 2 GB in a 32-bit computer, InnoDB would write log in a wrong position. That could make crash recovery and InnoDB Hot Backup to fail.

- Fixed a bug : index cursor restoration could theoretically fail.

### C.9.24. MySQL/InnoDB-4.0.8, 7 janvier 2003

- InnoDB now supports also FOREIGN KEY (...) REFERENCES ...(...) [ON UPDATE CASCADE | ON UPDATE SET NULL | ON UPDATE RESTRICT | ON UPDATE NO ACTION].

- Tables and indexes now reserve 4 % less space in the tablespace. Also existing tables reserve less space. By upgrading to 4.0.8 you will see more free space in "InnoDB free" in SHOW TABLE STATUS.

- Fixed bugs: updating the PRIMARY KEY of a row would generate a foreign key error on all FOREIGN KEYs which referenced secondary keys of the row to be updated. Also, if a referencing FOREIGN KEY constraint only referenced the first columns in an index, and there were more columns in that index, updating the additional columns generated a foreign key error.

- Fixed a bug : if an index contains some column twice, and that column is updated, the table will become corrupt. From now on InnoDB prevents creation of such indexes.

- Fixed a bug : removed superfluous error 149 and 150 printouts from the .err log when a locking SELECT caused a deadlock or a lock wait timeout.

- Fixed a bug : an assertion in btr0sea.c, in function btr_search_info_update_slow could theoretically fail in a race of 3 threads.

- Fixed a bug : one could not switch a session transaction isolation level back to REPEATABLE READ after setting it to something else.

### C.9.25. MySQL/InnoDB-4.0.7, 26 décembre 2002

- InnoDB in 4.0.7 is essentially the same as in 4.0.6.

### C.9.26. MySQL/InnoDB-4.0.6, 19 décembre 2002

- Since innodb_log_arch_dir has no relevance under MySQL, there is no need to specify it any more in my.cnf.

- LOAD DATA INFILE in AUTOCOMMIT=1 mode no longer does implicit commits for each 1 MB of written binlog.

- Fixed a bug introduced in 4.0.4: LOCK TABLES ... READ LOCAL should not set row locks on the rows read. This caused deadlocks and lock wait timeouts in mysqldump.

- Fixed two bugs introduced in 4.0.4: in AUTO_INCREMENT, REPLACE could cause the counter to be left 1 too low. A deadlock or a lock wait timeout could cause the same problem.

- Fixed a bug : TRUNCATE on a TEMPORARY table crashed InnoDB.

- Fixed a bug introduced in 4.0.5: if binlogging was not switched on, INSERT INTO ... SELECT ... or CREATE TABLE ... SELECT ... could cause InnoDB to hang on a semaphore created in btr0sea.c, line 128. Workaround: switch binlogging on.

- Fixed a bug : in replication issuing SLAVE STOP in the middle of a multi-statement transaction could cause that SLAVE START would only perform a part of the transaction. A similar error could occur if the slave crashed and was restarted.

### C.9.27. MySQL/InnoDB-3.23.54, 12 dcembre 2003

- Fixed a bug : the InnoDB range estimator greatly exaggerated the size of a short index range if the paths to the endpoints of the range in the index tree happened to branch already in the root. This could cause unnecessary table scans in SQL queries.

- Fixed a bug : ORDER BY could fail if you had not created a primary key to a table, but had defined several indexes of which at least one was a UNIQUE index with all its columns declared as NOT NULL.

- Fixed a bug : a lock wait timeout in connection with ON DELETE CASCADE could cause corruption in indexes.

- Fixed a bug : if a SELECT was done with a unique key from a primary index, and the search matched to a delete-marked record, InnoDB could erroneously return the NEXT record.

- Fixed a bug introduced in 3.23.53: LOCK TABLES ... READ LOCAL should not set row locks on the rows read. This caused deadlocks and lock wait timeouts in mysqldump.

- Fixed a bug : if an index contains some column twice, and that column is updated, the table will become corrupt. From now on InnoDB prevents creation of such indexes.

### C.9.28. MySQL/InnoDB-4.0.5, 18 novembre 2002

- InnoDB now supports also transaction isolation levels READ COMMITTED and READ UNCOMMITTED. READ COMMITTED more closely emulates Oracle and makes porting of applications from Oracle to MySQL easier.

- Deadlock resolution is now selective: we try to pick as victims transactions with less modified or inserted rows.

- FOREIGN KEY definitions are now aware of the lower_case_table_names setting in my.cnf.

- SHOW CREATE TABLE does not output the database name to a FOREIGN KEY definition if the referred table is in the same database as the table.

- InnoDB does a consistency check to most index pages before writing them to a datafile.

- If you set innodb_force_recovery > 0, InnoDB tries to jump over corrupt index records and pages when doing SELECT * FROM table. This helps in dumping.

- InnoDB now again uses asynchronous unbuffered I/O in Windows 2000 and XP; only unbuffered simulated async I/O in NT, 95/98/ME.

- Fixed a bug : the InnoDB range estimator greatly exaggerated the size of a short index range if the paths to the endpoints of the range in the index tree happened to branch already in the root. This could cause unnecessary table scans in SQL queries. The fix will also be backported to 3.23.54.

- Fixed a bug present in 3.23.52, 4.0.3, 4.0.4: InnoDB startup could take very long or even crash on some Windows 95/98/ME computers.

- Fixed a bug : the AUTO-INC lock was held to the end of the transaction if it was granted after a lock wait. This could cause unnecessary deadlocks.

- Fixed a bug : if SHOW INNODB STATUS, innodb_monitor, or innodb_lock_monitor had to print several hundred transactions in one report, and the output became truncated, InnoDB would hang, printing to the error log many waits for a mutex created at srv0srv.c, line 1621.

- Fixed a bug : SHOW INNODB STATUS on Unix always reported average file read size as 0 bytes.

- Fixed a potential bug in 4.0.4: InnoDB now does ORDER BY ... DESC like MyISAM.

- Fixed a bug : DROP TABLE could cause crash or a hang if there was a rollback concurrently running on the table. The fix will only be backported to 3.23 if this appears a real problem for users.

- Fixed a bug : ORDER BY could fail if you had not created a primary key to a table, but had defined several indexes of which at least one was a UNIQUE index with all its columns declared as NOT NULL.

- Fixed a bug : a lock wait timeout in connection with ON DELETE CASCADE could cause corruption in indexes.

- Fixed a bug : if a SELECT was done with a unique key from a primary index, and the search matched to a delete-marked record, InnoDB could return the NEXT record.

- Outstanding bugs: in 4.0.4 two bugs were introduced to AUTO_INCREMENT. REPLACE can cause the counter to be left 1 too low. A deadlock or a lock wait timeout can cause the same problem. These will be fixed in 4.0.6.

### C.9.29. MySQL/InnoDB-3.23.53, 9 octobre 2002

- We again use unbuffered disk I/O to datafiles in Windows. Windows XP and Windows 2000 read performance seems to be very poor with normal I/O.

- Tuned range estimator so that index range scans are preferred over full index scans.

- Allow dropping and creating a table even if innodb_force_recovery is set. One can use this to drop a table which would cause a crash in rollback or purge, or if a failed table import causes a runaway rollback in recovery.

- Fixed a bug present in 3.23.52, 4.0.3, 4.0.4: InnoDB startup could take very long or even crash on some Windows 95/98/ME computers.

- Fixed a bug : fast shutdown (which is the default) sometimes was slowed down by purge and insert buffer merge.

- Fixed a bug : doing a big SELECT from a table where no rows were visible in a consistent read could cause a very long (> 600 seconds) semaphore wait in btr0cur.c line 310.

- Fixed a bug : the AUTO-INC lock was held to the end of the transaction if it was granted after a lock wait. This could cause unnecessary deadlocks.

- Fixed a bug : if you created a temporary table inside LOCK TABLES, and used that temporary table, that caused an assertion failure in ha_innobase.cc.

- Fixed a bug : if SHOW INNODB STATUS, innodb_monitor, or innodb_lock_monitor had to print several hundred transactions in one report, and the output became truncated, InnoDB would hang, printing to the error log many waits for a mutex created at srv0srv.c, line 1621.

- Fixed a bug : SHOW INNODB STATUS on Unix always reported average file read size as 0 bytes.

### C.9.30. MySQL/InnoDB-4.0.4, 2 octobre 2002

- We again use unbuffered disk I/O in Windows. Windows XP and Windows 2000 read performance seems to be very poor with normal I/O.

- Increased the max key length of InnoDB tables from 500 to 1024 bytes.

- Increased the table comment field in SHOW TABLE STATUS so that up to 16000 characters of foreign key definitions can be printed there.

- The auto-increment counter is no longer incremented if an insert of a row immediately fails in an error.

- Allow dropping and creating a table even if innodb_force_recovery is set. One can use this to drop a table which would cause a crash in rollback or purge, or if a failed table import causes a runaway rollback in recovery.

- Fixed a bug : Using ORDER BY primarykey DESC in 4.0.3 causes an assertion failure in btr0pcur.c, line 203.

- Fixed a bug : fast shutdown (which is the default) sometimes was slowed down by purge and insert buffer merge.

- Fixed a bug : doing a big SELECT from a table where no rows were visible in a consistent read could cause a very long (> 600 seconds) semaphore wait in btr0cur.c line 310.

- Fixed a bug : if the MySQL query cache was used, it did not get invalidated by a modification done by ON DELETE CASCADE or ...SET NULL.

- Fixed a bug : if you created a temporary table inside LOCK TABLES, and used that temporary table, that caused an assertion failure in ha_innodb.cc.

- Fixed a bug : if you set innodb_flush_log_at_trx_commit to 1, SHOW VARIABLES would show its value as 16 million.

### C.9.31. MySQL/InnoDB-4.0.3, 28 août 2002

- Removed unnecessary deadlocks when inserts have to wait for a locking read, update, or delete to release its next-key lock.

- The MySQL `HANDLER` SQL commands now work also for `InnoDB` type tables. `InnoDB` does the `HANDLER` reads always as consistent reads. `HANDLER` is a direct access path to read individual indexes of tables. In some cases `HANDLER` can be used as a substitute of server-side cursors.

- Fixed a bug in 4.0.2: even a simple insert could crash the AIX version.

- Fixed a bug : if you used in a table name characters whose code is > 127, in DROP TABLE InnoDB could assert on line 155 of pars0sym.c.

- Compilation from source now provides a working version both on HP-UX-11 and HP-UX-10.20. The source of 4.0.2 worked only on 11, and the source of 3.23.52 only on 10.20.

- Fixed a bug : if compiled on 64-bit Solaris, InnoDB produced a bus error at startup.

### C.9.32. MySQL/InnoDB-3.23.52, 16 août 2002

- The feature set of 3.23 will be frozen from this version on. New features will go the 4.0 branch, and only bug fixes will be made to the 3.23 branch.

- Many CPU-bound join queries now run faster. On Windows also many other CPU-bound queries run faster.

- A new SQL command SHOW INNODB STATUS returns the output of the InnoDB Monitor to the client. The InnoDB Monitor now prints detailed information on the latest detected deadlock.

- InnoDB made the SQL query optimizer to avoid too much index-only range scans and choose full table scans instead. This is now fixed.

- `BEGIN` and `COMMIT` are now added in the binlog around transactions. The MySQL replication now respects transaction borders: a user will no longer see half transactions in replication slaves.

- A replication slave now prints in crash recovery the last master binlog position it was able to recover to.

- A new setting innodb_flush_log_at_trx_commit=2 makes InnoDB to write the log to the operating system file cache at each commit. This is almost as fast as the setting innodb_flush_log_at_trx_commit=0, and the setting 2 also has the nice feature that in a crash where the operating system does not crash, no committed transaction is lost. If the operating system crashes or there is a power outage, then the setting 2 is no safer than the setting 0.

- Added checksum fields to log blocks.

- SET FOREIGN_KEY_CHECKS=0 helps in importing tables in an arbitrary order which does not respect the foreign key rules.

- SET UNIQUE_CHECKS=0 speeds up table imports into InnoDB if you have UNIQUE constraints on secondary indexes. This flag should be used only if you are certain that the input records contain no UNIQUE constraint violations.

- SHOW TABLE STATUS now lists also possible ON DELETE CASCADE or ON DELETE SET NULL in the comment field of the table.

- When CHECK TABLE is run on any InnoDB type table, it now checks also the adaptive hash index for all tables.

- If you defined ON DELETE CASCADE or SET NULL and updated the referenced key in the parent row, InnoDB deleted or updated the child row. This is now changed to conform to SQL-92: you get the error 'Cannot delete parent row'.

- Improved the auto-increment algorithm: now the first insert or SHOW TABLE STATUS initializes the auto-increment counter for the table. This removes almost all surprising deadlocks caused by SHOW TABLE STATUS.

- Aligned some buffers used in reading and writing to datafiles. This allows using unbuffered raw devices as datafiles in Linux.

- Fixed a bug : If you updated the primary key of a table so that only the case of characters changed, that could cause assertion failures, mostly in page0page.ic line 515.

- Fixed a bug : If you delete or update a row referenced in a foreign key constraint and the foreign key check has to wait for a lock, then the check may report an erroneous result. This affects also the ON DELETE... operation.

- Fixed a bug : A deadlock or a lock wait timeout error in InnoDB causes InnoDB to roll back the whole transaction, but MySQL could still write the earlier SQL statements to the binlog, even though InnoDB rolled them back. This could, for example, cause replicated databases to get out-of-sync.

- Fixed a bug : If the database happened to crash in the middle of a commit, then the recovery might leak tablespace pages.

- Fixed a bug : If you specified a non-latin1 character set in my.cnf, then, in contrary to what is stated in the manual, in a foreign key constraint a string type column had to have the same length specification in the referencing table and the referenced table.

- Fixed a bug : DROP TABLE or DROP DATABASE could fail if there simultaneously was a CREATE TABLE running.

- Fixed a bug : If you configured the buffer pool bigger than 2 GB in a 32-bit computer, InnoDB would assert in buf0buf.ic line 214.

- Fixed a bug : on 64-bit computers updating rows which contained the SQL NULL in some column could cause the undo log and the ordinary log to become corrupt.

- Fixed a bug : innodb_log_monitor caused a hang if it suppressed lock prints for a page.

- Fixed a bug : in the HP-UX-10.20 version mutexes would leak and cause race conditions and crashes in any part of InnoDB code.

- Fixed a bug : if you ran in the AUTOCOMMIT mode, executed a SELECT, and immediately after that a RENAME TABLE, then RENAME would fail and MySQL would complain about error 1192.

- Fixed a bug : if compiled on 64-bit Solaris, InnoDB produced a bus error at startup.

### C.9.33. MySQL/InnoDB-4.0.2, 10 juillet 2002

- InnoDB is essentially the same as InnoDB-3.23.51.

- If no innodb_data_file_path is specified, InnoDB at the database creation now creates a 10 MB auto-extending datafile ibdata1 to the datadir of MySQL. In 4.0.1 the file was 64 MB and not auto-extending.

### C.9.34. MySQL/InnoDB-3.23.51, 12 juin 2002

- Fixed a bug : a join could result in a seg fault in copying of a BLOB or TEXT column if some of the BLOB or TEXT columns in the table contained SQL NULL values.

- Fixed a bug : if you added self-referential foreign key constraints with ON DELETE CASCADE to tables and a row deletion caused InnoDB to attempt the deletion of the same row twice because of a cascading delete, then you got an assertion failure.

- Fixed a bug : if you use MySQL 'user level locks' and close a connection, then InnoDB may assert in ha_innobase.cc, line 302.

### C.9.35. MySQL/InnoDB-3.23.50, 23 avril 2002

- InnoDB now supports an auto-extending last datafile. You do not need to preallocate the whole datafile at the database startup.

- Made several changes to facilitate the use of the InnoDB Hot Backup tool. It is a separate non-free tool you can use to take online backups of your database without shutting down the server or setting any locks.

- If you want to run the InnoDB Hot Backup tool on an auto-extending datafile you have to upgrade it to version ibbackup-0.35.

- The log scan phase in crash recovery will now run much faster.

- Starting from this server version, the hot backup tool truncates unused ends in the backup InnoDB datafiles.

- To allow the hot backup tool to work, on Windows we no longer use unbuffered I/O or native async I/O; instead we use the same simulated async I/O as on Unix.

- You can now define the ON DELETE CASCADE or ON DELETE SET NULL clause on foreign keys.

- FOREIGN KEY constraints now survive ALTER TABLE and CREATE INDEX.

- We suppress the FOREIGN KEY check if any of the column values in the foreign key or referenced key to be checked is the SQL NULL. This is compatible with Oracle, for example.

- SHOW CREATE TABLE now lists also foreign key constraints. Also mysqldump no longer forgets about foreign keys in table definitions.

- You can now add a new foreign key constraint with ALTER TABLE ... ADD CONSTRAINT FOREIGN KEY (...) REFERENCES ... (...).

- FOREIGN KEY definitions now allow backquotes around table and column names.

- MySQL command SET TRANSACTION ISOLATION LEVEL ... has now the following effect on InnoDB tables: if a transaction is defined as SERIALIZABLE then InnoDB conceptually adds LOCK IN SHARE MODE to all consistent reads. If a transaction is defined to have any other isolation level, then InnoDB obeys its default locking strategy which is REPEATABLE READ.

- SHOW TABLE STATUS no longer sets an x-lock at the end of an auto-increment index if the auto-increment counter has already been initialized. This removes in almost all cases the surprising deadlocks caused by SHOW TABLE STATUS.

- Fixed a bug : in a CREATE TABLE statement the string 'foreign' followed by a non-space character confused the FOREIGN KEY parser and caused table creation to fail with errno 150.

### C.9.36. MySQL/InnoDB-3.23.49, 17 février 2002

- Fixed a bug : if you called DROP DATABASE for a database on which there simultaneously were running queries, the MySQL server could crash or hang. Crashes fixed, but a full fix has to wait some changes in the MySQL layer of code.

- Fixed a bug : on Windows one had to put the database name in lower case for DROP DATABASE to work. Fixed in 3.23.49: case no longer matters on Windows. On Unix the database name remains case-sensitive.

- Fixed a bug : if one defined a non-latin1 character set as the default character set, then definition of foreign key constraints could fail in an assertion failure in dict0crea.c, reporting an internal error 17.

### C.9.37. MySQL/InnoDB-3.23.48, 9 février 2002

- Tuned the SQL optimizer to favor more often index searches over table scans.

- Fixed a performance problem when several large SELECT queries are run concurrently on a multiprocessor Linux computer. Large CPU-bound SELECT queries will now also generally run faster on all platforms.

- If MySQL binlogging is used, InnoDB now prints after crash recovery the latest MySQL binlog file name and the position in that file (= byte offset) InnoDB was able to recover to. This is useful, for example, when resynchronizing a master and a slave database in replication.

- Added better error messages to help in installation problems.

- One can now recover also MySQL temporary tables which have become orphaned inside the InnoDB tablespace.

- InnoDB now prevents a FOREIGN KEY declaration where the signedness is not the same in the referencing and referenced integer columns.

- Fixed a bug : calling SHOW CREATE TABLE or SHOW TABLE STATUS could cause memory corruption and make mysqld to crash. Especially at risk was mysqldump, because it calls frequently SHOW CREATE TABLE.

- Fixed a bug : if on Unix you did an ALTER TABLE to an InnoDB table and simultaneously did queries to it, mysqld could crash with an assertion failure in row0row.c, line 474.

- Fixed a bug : if inserts to several tables containing an auto-inc column were wrapped inside one LOCK TABLES, InnoDB asserted in lock0lock.c.

- In 3.23.47 we allowed several NULLS in a UNIQUE secondary index. But CHECK TABLE was not relaxed: it reports the table as corrupt. CHECK TABLE no longer complains in this situation.

- Fixed a bug : on Sparc and other high-endian processors SHOW VARIABLES showed innodb_flush_log_at_trx_commit and other boolean-valued startup parameters always OFF even if they were switched on.

- Fixed a bug : if you ran mysqld-max-nt as a service on Windows NT/2000, the service shutdown did not always wait long enough for the InnoDB shutdown to finish.

### C.9.38. MySQL/InnoDB-3.23.47, 28 décembre 2001

- Recovery happens now faster, especially in a lightly loaded system, because background checkpointing has been made more frequent.

- InnoDB allows now several similar key values in a UNIQUE secondary index if those values contain SQL NULLs. Thus the convention is now the same as in MyISAM tables.

- InnoDB gives a better row count estimate for a table which contains BLOBs.

- In a FOREIGN KEY constraint InnoDB is now case-insensitive to column names, and in Windows also to table names.

- InnoDB allows a FOREIGN KEY column of CHAR type to refer to a column of VARCHAR type, and vice versa. MySQL silently changes the type of some columns between CHAR and VARCHAR, and these silent changes do not hinder FOREIGN KEY declaration any more.

- Recovery has been made more resilient to corruption of log files.

- Unnecessary statistics calculation has been removed from queries which generate a temporary table. Some ORDER BY and DISTINCT queries will now run much faster.

- MySQL now knows that the table scan of an InnoDB table is done through the primary key. This will save a sort in some ORDER BY queries.

- The maximum key length of InnoDB tables is again restricted to 500 bytes. The MySQL interpreter is not able to handle longer keys.

- The default value of innodb_lock_wait_timeout was changed from infinite to 50 seconds, the default value of innodb_file_io_threads from 9 to 4.

### C.9.39. MySQL/InnoDB-4.0.1, 3 décembre 2001

- InnoDB is the same as in 3.23.47.

- In 4.0.0 the MySQL interpreter did not know the syntax LOCK IN SHARE MODE. This has been fixed.

- In 4.0.0 multiple-table delete did not work for transactional tables. This has been fixed.

### C.9.40. MySQL/InnoDB-3.23.46, 30 novembre 2001

- This is the same as 3.23.45.

### C.9.41. MySQL/InnoDB-3.23.45, 23 novembre 2001

- This is a bugfix release.

- In versions 3.23.42-.44 when creating a table on Windows you have to use lower case letters in the database name to be able to access the table. Fixed in 3.23.45.

- InnoDB now flushes stdout and stderr every 10 seconds: if these are redirected to files, the file contents can be better viewed with an editor.

- Fixed an assertion failure in .44, in trx0trx.c, line 178 when you drop a table which has the .frm file but does not exist inside InnoDB.

- Fixed a bug in the insert buffer. The insert buffer tree could get into an inconsistent state, causing a crash, and also crashing the recovery. This bug could appear especially in large table imports or alterations.

- Fixed a bug in recovery: InnoDB could go into an infinite loop constantly printing a warning message that it cannot find free blocks from the buffer pool.

- Fixed a bug : when you created a temporary table of the InnoDB type, and then used ALTER TABLE to it, the MySQL server could crash.

- Prevented creation of MySQL system tables 'mysql.user', 'mysql.host', or 'mysql.db', in the InnoDB type.

- Fixed a bug which can cause an assertion failure in 3.23.44 in srv0srv.c, line 1728.

### C.9.42. MySQL/InnoDB-3.23.44, 2 novembre 2001

- You can define foreign key constraints on InnoDB tables. An example: FOREIGN KEY (col1) REFERENCES table2(col2).

- You can create > 4 GB datafiles in those file systems that allow it.

- Improved InnoDB monitors, including a new innodb_table_monitor which allows you to print the contents of the InnoDB internal data dictionary.

- DROP DATABASE will now work also for InnoDB tables.

- Accent characters in the default character set latin1 will be ordered according to the MySQL ordering.<br> NOTE: if you are using latin1 and have inserted characters whose code is > 127 to an indexed CHAR column, you should run CHECK TABLE on your table when you upgrade to 3.23.43, and drop and reimport the table if CHECK TABLE reports an error!

- InnoDB will calculate better table cardinality estimates.

- Change in deadlock resolution: in .43 a deadlock rolls back only the SQL statement, in .44 it will roll back the whole transaction.

- Deadlock, lock wait timeout, and foreign key constraint violations (no parent row, child rows exist) now return native MySQL error codes 1213, 1205, 1216, 1217, respectively.

- A new my.cnf parameter innodb_thread_concurrency helps in performance tuning in high concurrency environments.

- A new my.cnf option innodb_force_recovery will help you in dumping tables from a corrupted database.

- A new my.cnf option innodb_fast_shutdown will speed up shutdown. Normally InnoDB does a full purge and an insert buffer merge at shutdown.

- Raised maximum key length to 7000 bytes from a previous limit of 500 bytes.

- Fixed a bug in replication of auto-inc columns with multiline inserts.

- Fixed a bug when the case of letters changes in an update of an indexed secondary column.

- Fixed a hang when there are > 24 datafiles.

- Fixed a crash when MAX(col) is selected from an empty table, and col is a not the first column in a multi-column index.

- Fixed a bug in purge which could cause crashes.

### C.9.43. MySQL/InnoDB-3.23.43, 4 octobre 2001

- This is essentially the same as InnoDB-3.23.42.

### C.9.44. MySQL/InnoDB-3.23.42, 9 septembre 2001

- Fixed a bug which corrupted the table if the primary key of a > 8000-byte row was updated.

- There are now 3 types of InnoDB Monitors: innodb_monitor, innodb_lock_monitor, and innodb_tablespace_monitor. innodb_monitor now prints also buffer pool hit rate and the total number of rows inserted, updated, deleted, read.

- Fixed a bug in RENAME TABLE.

- Fixed a bug in replication with an auto-increment column.

### C.9.45. MySQL/InnoDB-3.23.41, 13 août 2001

- Support for < 4 GB rows. The previous limit was 8000 bytes.

- Use the doublewrite file flush method.

- Raw disk partitions supported as datafiles.

- InnoDB Monitor.

- Several hang bugs fixed and an `ORDER BY` bug ('Sort aborted') fixed.

### C.9.46. MySQL/InnoDB-3.23.40, 16 juillet 2001

- Only a few rare bugs fixed.

### C.9.47. MySQL/InnoDB-3.23.39, 13 juin 2001

- `CHECK TABLE` now works for `InnoDB` tables.

- A new `my.cnf` parameter `innodb_unix_file_flush_method` introduced. It can be used to tune disk write performance.

- An auto-increment column now gets new values past the transaction mechanism. This saves CPU time and eliminates transaction deadlocks in new value assignment.

- Several bug fixes, most notably the rollback bug in 3.23.38.

### C.9.48. MySQL/InnoDB-3.23.38, 12 mai 2001

- The new syntax `SELECT ... LOCK IN SHARE MODE` is introduced.

- `InnoDB` now calls `fsync()` after every disk write and calculates a checksum for every database page it writes or reads, which will reveal disk defects.

- Several bug fixes.

## C.10. Historique de `MySQL Cluster`

Note : cette section n'est pas traduite en fran¸ais.

### C.10.1. MySQL Cluster-4.1.11 (01 Apr 2005)

Fonctionnalité ajoutée ou modifiée :

Bogues corrigés :

- (Bug#9435) TIMESTAMP columns don't update

- (Bug#8753) Invalid schema object version after dropping index (crash fixed, currently retry required)

- (Bug#8557) ndbd does not get same nodeid on restart

- (Bug#8556) corrupt ndb_mgm show printout for certain configurations

- (Bug#8167) cluster shared memory and mysqld signal usage clash

### C.10.2. MySQL Cluster-4.1.10 (12 Feb 2005)

Fonctionnalité ajoutée ou modifiée :

Bogues corrigés :

- (Bug#8284) Out of fragment memory in DBACC

- (Bug#8262) Node crash due to bug in DBLQH

- (Bug#8208) node restart fails on Aix 5.2

- (Bug#8167) cluster shared memory and mysqld signal usage clash

- (Bug#8101) unique index and error 4209 while selecting

- (Bug#8070) (Bug#7937) (Bug#6716) various ndb_restore core dumps on HP-UX

- (Bug#8010) 4006 forces MySQL Node Restart

- (Bug#7928) out of connection objects

- (Bug#7898) mysqld crash with ndb (solaris)

- (Bug#7864) Not possible to have more than 4.5G data memory

### C.10.3. MySQL Cluster-4.1.9 (13 Jan 2005)

Fonctionnalité ajoutée ou modifiée :

- New implementation of shared memory transporter.

- Cluster automatically configures shared memory transporter if possible.

- Cluster prioritizes usage of transporters with shared memory and localhost TCP

- Added switches to control the above functions, `ndb-shm` and `ndb-optimized-node-selection`.

Bogues corrigés :

- (Bug#7805) config.ini parsing error

- (Bug#7798) Running range scan after alter table in different thread causes node failure

- (Bug#7761) Alter table does not autocommit

- (Bug#7725) Indexed DATETIME Columns Return Random Results

- (Bug#7660) START BACKUP does not increment BACKUP-ID (Big Endian machines)

- (Bug#7593) Cannot Create A Large NDB Data Warehouse

- (Bug#7480) Mysqld crash in ha_ndbcluster using Query Browser

- (Bug#7470) shared memory transporter does not connect

- (Bug#7396) Primary Key not working in NDB Mysql Clustered table (solaris)

- (Bug#7379) ndb restore fails to handle blobs and multiple databases

- (Bug#7346) ndb_restore enters infinite loop

- (Bug#7340) Problem for inserting data into the Text field on utf8

- (Bug#7124) ndb_mgmd is aborted on startup when using SHM connection

### C.10.4. MySQL Cluster-4.1.8 (14 Dec 2004)

Fonctionnalité ajoutée ou modifiée :

- Default port for ndb_mgmd was changed to 1186 (from 2200) as this port number was officially assigned to MySQL Cluster by IANA.

- New command in ndb_mgm, PURGE STALE SESSIONS, as a workaround for cases where nodes fail to allocate a node id even if it is free to use.

- New command in ndb_mgm, CONNECT.

- The ndb executables have been changed to make use of the regular MySQL command line option parsing features. See Section 16.5.5, « Options des commandes pour le cluster MySQL » for notes on changes.

- As bonus of the above you can now specify all command line options in `my.cnf` using the executable names as sections, i.e. `[ndbd]`, `[ndb_mgmd]`, `[ndb_mgm]`, `[ndb_restore]` etc.

            [ndbd]
            ndb-connectstring=myhost.domain.com:1234
            [ndb_mgm]
            ndb-connectstring=myhost.domain.com:1234

- Added use of section `[mysql_cluster]` in `my.cnf`. All cluster executables, including mysqld, parse this section. Convenient place to put e.g. `ndb-connectstring` so that it only needs to be specified once.

- Added cluster log info events on allocation and deallocation of nodeid's.

- Added cluster log info events on connection refuse as a result of version mismatch.

- Extended connectstring syntax to allow for leaving the port number out. E.g. `ndb-connectstring|connect-string=myhost1,myhost2,myhost3` is a valid connectstring and connect occurs on default port 1186.

- Clear text ndb error messages provided also for error codes that are mapped to corresponding mysql error codes, by executing `SHOW WARNINGS` after an error has occured which relates to the ndb storage engine.

- Significant performance improvements done for read performance, especially for blobs.

- Added some variables for performance tuning, `ndb_force_send` and `ndb_use_exact_count`. Do `show variables like 'ndb%';` in mysql client for listing. Use `set` command to alter variables.

- Added variables to set some options, `ndb_use_transactions` and `ndb_autoincrement_prefetch_sz`.

Bogues corrigés :

- (Bug#7303) ndb_mgm: Trying to set CLUSTERLOG for a specific node id core dumps

- (Bug#7193) start backup gives false error printout

- (Bug#7153) Cluster nodes don't report error on endianness mismatch

- (Bug#7152) ndb_mgmd segfaults on incorrect HostName in configuration

- (Bug#7104) clusterlog filtering and level setting broken

- (Bug#6995) ndb_recover on varchar fields results in changing case of data

- (Bug#6919) all status only shows 2 nodes on a 8-node cluster

- (Bug#6871) DBD execute failed: Got error 897 'Unknown error code' from ndbcluster

- (Bug#6794) Wrong outcome of update operation of ndb table

- (Bug#6791) Segmentation fault when config.ini is not correctly set

- (Bug#6775) failure in acc when running many mysql clients

- (Bug#6696) ndb_mgm command line options inconsistent with behavior

- (Bug#6684) ndb_restore doesn't give error messages if inproper command given

- (Bug#6677) ndb_mgm can crash on "ALL CLUSTERLOG"

- (Bug#6538) Error code returned when select max() on empty table with index

- (Bug#6451) failing create table givers "ghost" tables which are impossible to remove

- (Bug#6435) strange behavior of left join

- (Bug#6426) update with long pk fails

- (Bug#6398) update of primary key fails

- (Bug#6354) mysql does not complain about --ndbcluster option when NDB is not compiled in

- (Bug#6331) INSERT IGNORE .. SELECT breaks subsequent inserts

- (Bug#6288) cluster nodes crash on data import

- (Bug#6031) To drop database you have to execute DROP DATABASE command twice

- (Bug#6020) LOCK TABLE + delete returns error 208

- (Bug#6018) REPLACE does not work for BLOBs + NDB

- (Bug#6016) Strange crash with blobs + different DATABASES

- (Bug#5973) ndb table belonging to different database shows up in show tables

- (Bug#5872) ALTER TABLE with blob from ndb table to myisam fails

- (Bug#5844) Failing mysql-test-run leaves stray NDB processes behind

- (Bug#5824) HELP text messed up in ndb_mgm

- (Bug#5786) Duplicate key error after restore

- (Bug#5785) lock timeout during concurrent update

- (Bug#5782) Unknown error when using LIMIT with ndb table

- (Bug#5756) RESTART node from ndb_mgm fails

- A few more not reported bugs fixed

### C.10.5. MySQL Cluster-4.1.7, (23 Octobre 2004)

Fonctionnalités ajoutées ou modifiées :

- Optimization 1: Improved performance on index scans. Measured 30% performance increase on query which do large amounts of index scans.

- Optimization 2: Improved performance on primary key lookups. Around double performance for autocommitted primary key lookups.

- Optimization 3: Improved performance when using blobs by avoiding usage of exclusive locks for blobs.

Bogues corrigés :

- A few bugs fixed.

### C.10.6. MySQL Cluster-4.1.6, 10 octobre 2004

Fonctionnalité ajoutée ou modifiée :

- Limited character set support for storage engine NDBCLUSTER:

  Char set | Collation
  big5 | big5_chinese_ci
  | big5_bin
  binary | binary
  euckr | euckr_korean_ci
  | euckr_bin
  gb2312 | gb2312_chinese_ci
  | gb2312_bin
  gbk | gbk_chinese_ci
  | gbk_bin
  latin1 | latin1_swedish_ci
  | latin1_bin
  sjis | sjis_japanese_ci
  | sjis_bin
  tis620 | tis620_bin
  ucs2 | ucs2_general_ci
  | ucs2_bin
  ujis | ujis_japanese_ci
  | ujis_bin
  utf8 | utf8_general_ci
  | utf8_bin

- The SCI Transporter has been brought up-to-date with all changes and now works and has been documented as well.

- Optimizations when several clients to a MySQL Server access ndb tables.

- Added more checks and warnings for erroneous and unappropriate cluster configurations.

- `SHOW TABLES` now directly shows ndb tables created on a different mysql server, i.e. without a prior table access.

- Enhanced support for starting MySQL Server independently of ndbd and ndb_mgmd.

Bogues corrigés :

- Quite a few bugs fixed.

### C.10.7. MySQL Cluster-4.1.5, 16 septembre 2004

Fonctionnalité ajoutée ou modifiée :

- Many queries in MySQL Cluster are executed as range scans or full table scans. All queries that don't use a unique hash index or the primary hash index will use this access method. In a distributed system it is crucial that batching is properly performed.

  In previous version the batch size was fixed to 16 per storage node. In this version it is configurable per MySQL Server. So for queries using lots of large scans it is appropriate to set this parameter rather large and for queries using lots of small scans only fetching a small amount of records it is appropriate to set it low.

  The performance of queries can easily change as much as 40% based on how this variable is set.

  In future versions more logic will be made to assess the batch size on per query basis. Thus the semantics of this new configuration variable `ScanBatchSize` is likely to change.

- The fixed size overhead of the ndbd process was greatly decreased. Also overhead per operation record was greatly decreased and also overhead per table and index was greatly decreased.

  A number of new configuration variables was introduced to be able to configure more buffers in the system. Configuration variables to specify the number of tables, unique hash indexes and ordered indexes was introduced as well.

  New configuration variables: `MaxNoOfOrderedIndexes`, `MaxNoOfUniqueHashIndexes`

  Configuration variables no longer used: `MaxNoOfIndexes` (split into the two above).

- In previous versions `ALTER TABLE`, `TRUNCATE TABLE`, and `LOAD DATA` were performed as one big transaction. In this version, all those statements will be automatically separated into a number of transactions.

  This removes the limitation that one could not change very large tables due to the `MaxNoOfConcurrentOperations` parameter.

- The online backup feature of MySQL Cluster now also backs up the indexes such that the restore ensures that both data and indexes are restored.

- In previous versions it was not possible to use `NULL` in indexes. This is now possible in all indexes.

- Much work has been put onto making `AUTO_INCREMENT` features work as for other table handlers. Autoincrements as a partial key is still only supported by `MyISAM`.

- In previous version,s mysqld would crash if the cluster wasn't started and the `--ndbcluster` option was used. Now mysqld will handle cluster crashes and not started without crashing.

- The `-i` option for initial startup has been removed from ndbd. Initial startup still can be specified by using the `--initial` option. The reason is to ensure that it is clearer what takes place when using the `--initial` option. This option completely removes all data from the disk and should only be used at initial start, in certain software upgrade cases, and in some cases when node restarts don't work as a workaround.

- The management client (ndb_mgm) now has more commands and more information is printed in some commands such as `show`.

- In previous versions, the files were called `ndb_0..` when it wasn't possible to allocate a node ID when starting the node. To ensure that files are not so easily overwritten, these files are now named `ndb_pid..`, where pid is the process ID assigned by the OS.

- The default parameters have changed for ndb_mgmd and ndbd. Yn particular, they are now started as daemons by default. The `-n` option was removed since it could confusion as to whether its meaning is nostart or nodaemon.

- In the configuration file, you can now use `[NDBD]` as an alias for `[DB]`, `[MYSQLD]` as an alias for `[API]`, and `[NDB_MGMD]` as an alias for `[MGM]`.

- Many more checks of the consistency of the configuration have been introduced to provide quicker feedback on configuration errors.

- In the connect string, it is now possible to use both ‘`;`’ and ‘`,`’ as the separator between entries. So "nodeid=2,host=localhost:2200" is equivalent to "nodeid=2;host=localhost:2200".

  In the configuration, it is possible to use ‘`:`’ or ‘`=`’ as the assignment symbol. Thus `MaxNoOfOrderedIndexes : 128` and `MaxNoOfOrderedIndexes = 128` are equivalent.

- The configuration variable names are now case insensitive so `MaxNoOfOrderedIndexes: 128` is equivalent to `MAXNOOFORDEREDINDEXES = 128`.

- It is possible now to set the backup directory separately from the `FileSystemPath` by using the `BackupDir` config variable.

  Log files and trace files can now be put in any directory by setting the `DataDir` configuration variable.

  `FileSystemPath` is no longer mandatory and defaults to `DataDir`.

- It is now supported to perform queries involving tables from different databases in MySQL.

- It is now possible to update the primary key.

- The performance of the ordered index has been greatly improved, particularly the maintenance of the index at updates, inserts and deletes.

Bogues corrigés :

- Quite a few bugs fixed.

### C.10.8. MySQL Cluster-4.1.4, 31 août 2004

Fonctionnalité ajoutée ou modifiée :

- The names of the log files and trace files created by the ndbd and ndb_mgmd processes have changed.

- Support for the many `BLOB` data types was introduced in this version.

Bogues corrigés :

- Quite a few bugs were fixed in the 4.1.4 release.

### C.10.9. MySQL Cluster-5.0.1, 27 juillet 2004

Fonctionnalité ajoutée ou modifiée :

- This was the first MySQL Cluster release in 5.0. Actually almost all attention was on getting 4.1 stable so it is not recommended to use MySQL 5.0.1 for MySQL Cluster usage.

Bogues corrigés :

### C.10.10. MySQL Cluster-4.1.3, 28 juin 2004

Fonctionnalité ajoutée ou modifiée :

- This was the first MySQL Cluster release so all the functionality was new.

Bogues corrigés :

- Various bugs fixed in the development process leading up to 4.1.3.

## C.11. Historique de `MyODBC`

### C.11.1. Changes in MyODBC 3.51.12

Fonctionnalité ajoutée ou modifiée :

Bogues corrigés :

- `SQLColumns()` returned no information for tables that had a column named using a reserved word. (Bug#9539)

### C.11.2. Changes in MyODBC 3.51.11

Fonctionnalité ajoutée ou modifiée : No changes.

Bogues corrigés :

- `mysql_list_dbcolumns()` and `insert_fields()` were retrieving all rows from a table. Fixed the queries generated by these functions to return no rows. (Bug#8198)

- `SQLGetTypoInfo()` returned `tinyblob` for `SQL_VARBINARY` and nothing for `SQL_BINARY`. Fixed to return `varbinary` for `SQL_VARBINARY`, `binary` for `SQL_BINARY`, and `longblob` for `SQL_LONGVARBINARY`. (Bug#8138)

This is a translation of the MySQL Reference Manual that can be found at dev.mysql.com. The original Reference Manual is in English, and this translation is not necessarily as up to date as the English version.

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