Скачать MySQL 6.0.6 – бесплатный сервер баз данных

MySQL Community Server — программа для управления базами данных (СУБД). Распространяется под GNU General Public License и под собственной коммерческой лицензией, на выбор. MySQL является собственностью компании Sun Microsystems.

MySQL ето решением для малых и средних приложений. MySQL обычно используется в качестве сервера, к которому обращаются локальные или удалённые клиенты, однако в дистрибутив входит библиотека внутреннего сервера, позволяющая включать MySQL в автономные программы.

MySQL обеспечивается поддержкой большого количества типов таблиц: пользователи могут выбрать как таблицы типа MyISAM, поддерживающие полнотекстовый поиск, так и таблицы InnoDB, поддерживающие транзакции на уровне отдельных записей. Более того, СУБД MySQL поставляется со специальным типом таблиц EXAMPLE, демонстрирующим принципы создания новых типов таблиц. Благодаря открытой архитектуре и GPL – лицензированию, в СУБД MySQL постоянно появляются новые типы таблиц.

Что нового в MySQL 5.1.41

# Functionality added or changed:

* The InnoDB buffer pool is divided into two sublists: A new sublist containing blocks that are heavily used by queries, and an old sublist containing less-used blocks and from which candidates for eviction are taken. In the default operation of the buffer pool, a block when read in is loaded at the midpoint and then moved immediately to the head of the new sublist as soon as an access occurs. In the case of a table scan (such as performed for a mysqldump operation), each block read by the scan ends up moving to the head of the new sublist because multiple rows are accessed from each block. This occurs even for a one-time scan, where the blocks are not otherwise used by other queries. Blocks may also be loaded by the read-ahead background thread and then moved to the head of the new sublist by a single access. These effects can be disadvantageous because they push blocks that are in heavy use by other queries out of the new sublist to the old sublist where they become subject to eviction.

InnoDB Plugin now provides two system variables that enable LRU algorithm tuning:

- innodb_old_blocks_pct

Specifies the approximate percentage of the buffer pool used for the old block sublist. The range of values is 5 to 95. The default value is 37 (that is, 3/8 of the pool).

- innodb_old_blocks_time

# Bugs fixed:

* Important Change: Security Fix: Additional corrections were made for the symlink-related privilege problem originally addressed in MySQL 5.1.24. The original fix did not correctly handle the data directory path name if it contained symlinked directories in its path, and the check was made only at table-creation time, not at table-opening time later. (Bug#32167, CVE-2008-2079)
See also Bug#39277.

* Security Fix: MySQL clients linked against OpenSSL did not check server certificates presented by a server linked against yaSSL. (Bug#47320)

* Partitioning: An ALTER TABLE ... ADD PARTITION statement that caused open_files_limit to be exceeded led to a crash of the MySQL server. (Bug#46922)
See also Bug#47343.

* Partitioning: The cardinality of indexes on partitioned tables was calculated using the first partition in the table, which could result in suboptimal query execution plans being chosen. Now the partition having the most records is used instead, which should result in better use of indexes and thus improved performance of queries against partitioned tables in many if not most cases. (Bug#44059)

* Replication: This issue occurred in MySQL 5.1.40 only. (Bug#48297)

*Replication: When a session was closed on the master, temporary tables belonging to that session were logged with the wrong database names when either of the following conditions was true:

1. The length of the name of the database to which the temporary table belonged was greater than the length of the current database name.
2. The current database was not set.(Bug#48216)
See also Bug#46861, Bug#48297.

* Replication: When using row-based replication, changes to non-transactional tables that occurred early in a transaction were not immediately flushed upon committing a statement. This behavior could break consistency since changes made to non-transactional tables become immediately visible to other connections. (Bug#47678)
See also Bug#47287, Bug#46864, Bug#43929, Bug#46129.

* Replication: When mysqlbinlog --verbose was used to read a binary log that had been recorded using the row-based format, the output for events that updated some but not all columns of tables was not correct. (Bug#47323)

* Replication: When using the row-based format to replicate a transaction involving both transactional and non-transactional engines, which contained a DML statement affecting multiple rows, the statement failed; if this transaction was followed by a COMMIT, the master and the slave could diverge, because the statement was correctly rolled back on the master, but was applied on the slave. (Bug#47287)
See also Bug#46864.

* Replication: A problem with the BINLOG statement in the output of mysqlbinlog could break replication; statements could be logged with the server ID stored within events by the BINLOG statement rather than the ID of the running server. With this fix, the server ID of the server executing the statements can no longer be overridden by the server ID stored in the binary log's format description statement. (Bug#46640)
This regression was introduced by Bug#32407.

* Replication: When using statement-based replication and the transaction isolation level was set to READ COMMITTED or a less strict level, InnoDB returned an error even if the statement in question was filtered out according to the --binlog-do-db or --binlog-ignore-db rules in effect at the time. (Bug#42829)

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