Upgrading from an Advanced GPL RPM package to an Advanced RPM package did not work. Now on Linux it is possible to use rpm -U to replace any installed MySQL product by any other of the same release family. It is not necessary to remove the old produce with rpm -e first. (Bug #11886309)

MEMORY table creation time is now available in the CREATE_TIME column of the INFORMATION_SCHEMA.TABLES table and the Create_time column of SHOW TABLE STATUS output. (Bug #51655, Bug #11759349)

Performance; InnoDB: The process of deallocating the InnoDB Adaptive Hash Index was made faster, during shutdown or when turning off the AHI with the statement:

SET GLOBAL innodb_adaptive_hash_index=OFF;

(Bug #13006367, Bug #62487)

Performance; InnoDB: This fix improves the performance of instrumentation code for InnoDB buffer pool operations. (Bug #12950803, Bug #62294)

Performance; InnoDB: The InnoDB buffer pool management code was optimized for handling pages from compressed tables. This fixes a slowdown that could occur particularly during the warmup period for the buffer pool. (Bug #12610930, Bug #61341)

InnoDB: Fixed a compilation problem that affected the InnoDB source code with gcc 4.6.1. The affected InnoDB source file was btr/btr0cur.c. (Bug #13116045)

InnoDB: Lookups using secondary indexes could give incorrect matches under a specific set of conditions. The conditions involve an index defined on a column prefix, for a BLOB or other long column stored outside the index page, with a table using the Barracuda file format. (Bug #12601439, Bug #12543666)

InnoDB: An UPDATE statement for an InnoDB table could hang. The issue affects tables using the Barracuda file format and having multiple indexes on column prefixes. The size of an undo log record could exceed the page size, even though the total size of the column prefixes was less than the page size (usually 16KB). In MySQL 5.5 and higher, this error is now reported using the new code ER_UNDO_RECORD_TOO_BIG. In MySQL 5.1 with the InnoDB Plugin, this error is reported using the existing code ER_TOO_BIG_ROWSIZE. (Bug #12547647)

InnoDB: This fix corrects cases where the MySQL server could hang or abort with a long semaphore wait message. (This is a different issue than when these symptoms occurred during a CHECK TABLE statement.) (Bug #11766591, Bug #59733)

InnoDB: A timing issue could cause a crash while processing the SHOW ENGINE INNODB STATUS command. This issue only affected debug builds of the server. (Bug #11766546, Bug #59682)

Replication: Issuing the following statements, in the order shown, could cause a deadlock between the user thread and I/O thread:

START SLAVE;
STOP SLAVE SQL_THREAD;
START SLAVE;

(Bug #11878104)

References: See also Bug #44312, Bug #11752963, Bug #38715, Bug #38716.

Internal conversion of zero to binary and back could yield a result with incorrect precision. (Bug #12911710)

Valgrind warnings generated by filesort operations were fixed. (Bug #12856915)

Several improvements were made to the libedit library bundled with MySQL distributions, and that is available for all platforms that MySQL supports except Windows.

(Bug #12605400, Bug #12613725, Bug #12618092, Bug #12624155, Bug #12617651, Bug #12605388)

decimal_round() could cause a server exit when processing long numeric strings. (Bug #12563865)

With Valgrind enabled, InnoDB semaphore wait timeouts were too low and could expire. (Bug #11765460)

If MySQL was configured with --without-plugin-innobase and --with-plugin-innodb_plugin, to suppress building the built-in InnoDB storage engine and build the InnoDB Plugin instead, the innochecksum utility was not built. (Bug #47337, Bug #11755544)

On Fedora, certain accesses to /var/lib/mysql/HOSTNAME.err were blocked by SELinux policy, which made the server fail at startup with the message: Manager of pid-file quit without updating file (Bug #37165, Bug #12927740)

The help message for mysql_install_db did not indicate that it supports the --defaults-file, --defaults-extra-file and --no-defaults options. (Bug #58898, Bug #11765888)

myisampack could create corrupt FULLTEXT indexes when compressing tables. (Bug #53646, Bug #11761180)

An assertion designed to detect zero-length sort keys also was raised when the entire key set fit in memory. (Bug #58200, Bug #11765254)

A linking problem prevented the FEDERATED storage engine plugin from loading. (Bug #40942, Bug #11750417)

For FEDERATED tables, loss of connection to the remote table during some insert operations could cause a server crash. (Bug #34660, Bug #11747970)

OPTIMIZE TABLE could corrupt MyISAM tables if myisam_use_mmap was enabled. (Bug #49030, Bug #11757032)