MySQL 5.6.22 Overview and Highlights

MySQL 5.6.22 was recently released (it is the latest MySQL 5.6, is GA), and is available for download here.

For this release, there is 1 “Security Note”, 2 “Functionality Changed”, and 5 “Compilation Notes”, all benign, but let me address them:

  1. Security Note: The linked OpenSSL library for the MySQL Commercial Server has been updated from version 1.0.1h to version 1.0.1j. Issues fixed in the new version are described at http://www.openssl.org/news/vulnerabilities.html.
  2. Functionality Changed: Replication: The variable binlogging_impossible_mode has been renamed binlog_error_action. binlogging_impossible_mode is now deprecated. (Bug #19507567)
  3. Functionality Changed: Security: yaSSL was upgraded to version 2.3.5. (Bug #19695101)
  4. Compilation Notes: These are all rather minor, so I’ll spare the full entries here. However, if you build MySQL from source, it would be worth several minutes to read the 5 notes in the changelogs.

In addition to those, there were 46 other bug fixes:

  • 17 InnoDB
  •   9 Replication
  • 19 Miscellaneous
  •   1 Partitioning

The highlights for me are 6 of the InnoDB bugs, as 2 were regression bugs (crashing/corruption), 2 potentially corruption causing, another crashing, and 1 halting:

  1. InnoDB: An ALTER TABLE operation raised an assertion. When a foreign key object was removed from the dictionary cache, an incorrect foreign key object was removed from the rb-tree. (Bug #19908343) References: This bug is a regression of Bug #18806829.
  2. InnoDB: Pages with a checksum value of zero were incorrectly treated as empty pages. A page should only be considered empty if its checksum value and LSN field values are zero. (Bug #19500258, Bug #73689) References: This bug is a regression of Bug #17335427.
  3. InnoDB: The dict_set_corrupted() function attempted to update the clustered index of the SYS_INDEXES data dictionary table incorrectly. (Bug #19584379).
  4. InnoDB: The InnoDB data dictionary was not updated when a ALTER TABLE … CHANGE COLUMN operation changed the case of the column name. (Bug #19465984).
  5. InnoDB: A memory access violation caused fts_optimize_thread and mysqld to terminate. (Bug #19314480).
  6. InnoDB: A procedure, called from a function to perform an operation on a temporary table, caused the server to halt/stall. (Bug #19306524)

Conclusions:

So while there were no major changes, those 6 InnoDB bugs (2 being regression bugs) are definitely of concern, so I’d be sure to review these to see if you’re running an affected version, and consider upgrading if so.

And with the yaSSL updates, if you use SSL connections, you may want to consider upgrading as well.

The full 5.6.22 changelogs can be viewed here (which has more details about all of the bugs listed above):

http://dev.mysql.com/doc/relnotes/mysql/5.6/en/news-5-6-22.html

Hope this helps.