オリジナル版：http://lists.mysql.com/announce/995
最も普及しているオープンソースデータベース管理システムの新バージョンMySQL Community Server 5.6.25がリリースされました。MySQL 5.6.25は、プロダクションシステムでの使用をお勧めします。
MySQL 5.6の特徴としては、以下のようなものがあります。
・InnoDB、オプティマイザ、レプリケーション、パーティショニングの性能向上
・GTID（Global Transaction ID）の実装
・Performance_schemaの機能強化
その他詳細については、下記URLを参照してください。
http://dev.mysql.com/doc/refman/5.6/en/mysql-nutshell.html
新たなサーバにMySQL 5.6.25をインストール、または以前のMySQLリリースからMySQL 5.6.25にアップグレードする際の情報については、以下を参照してください。
http://dev.mysql.com/doc/refman/5.6/en/installing.html
下記のダウンロードページから、MySQLサーバのソースコード及び多数のプラットフォーム用バイナリが入手可能です
http://dev.mysql.com/downloads/
現時点ですべてのミラーサイトが最新であるとは限らないことに注意してください。
あるミラーサイトで本バージョンを見つけることができない場合は、後日再確認を行うか、別のダウンロード・サイトを選択してください。
フィードバック、バグレポート、バグ修正、パッチ等の情報をお待ちしておりますので、以下のページをご利用ください。
https://wikis.oracle.com/display/mysql/Contributing
以下のセクションは、MySQL5.6の前リリース以降のMySQLソースコードの変更を記載しています。これはオンラインでも閲覧可能です：
http://dev.mysql.com/doc/relnotes/mysql/5.6/en/news-5-6-25.html
以下は、追加または変更された機能です。
Changes in MySQL 5.6.25 (2015-05-29)
Functionality Added or Changed
* MySQL Enterprise Firewall operates on parser states and
does not work well together with the query cache, which
circumvents the parser. MySQL Enterprise Firewall now
checks whether the query cache is enabled. If so, it
displays a message that the query cache must be disabled
and does not load. (Bug #20913616)
* my_print_defaults now masks passwords. To display
passwords in cleartext, use the new --show option. (Bug
#19953365)
* MySQL distributions now include an innodb_stress suite of
test cases. Thanks to Mark Callaghan for the
contribution. (Bug #76347, Bug #20717127)
Bugs Fixed
* InnoDB; Partitioning: The CREATE_TIME column of the
INFORMATION_SCHEMA.TABLES table now shows the correct
table creation time for partitioned InnoDB tables. The
CREATE_TIME column of the INFORMATION_SCHEMA.PARTITIONS
table now shows the correct partition creation time for a
partition of partitioned InnoDB tables.
The UPDATE_TIME column of the INFORMATION_SCHEMA.TABLES
table now shows when a partitioned InnoDB table was last
updated by an INSERT, DELETE, or UPDATE. The UPDATE_TIME
column of the INFORMATION_SCHEMA.PARTITIONS table now
shows when a partition of a partitioned InnoDB table was
last updated. (Bug #69990, Bug #17299181)
* InnoDB: An assertion was raised on shutdown due to XA
PREPARE transactions holding explicit locks. (Bug
#20816223)
* InnoDB: The strict_* forms of innodb_checksum_algorithm
settings (strict_none, strict_innodb, and strict_crc32)
caused the server to halt when a non-matching checksum
was encountered, even if the non-matching checksum was
valid. For example, with
innodb_checksum_algorithm=strict_crc32, encountering a
valid innodb checksum caused the server to halt. Instead
of halting the server, a message is now printed to the
error log and the page is accepted as valid if it matches
an innodb, crc32 or none checksum. (Bug #20568464)
* InnoDB: The memcached set command permitted a negative
expire time value. Expire time is stored internally as an
unsigned integer. A negative value would be converted to
a large number and accepted. The maximum expire time
value is now restricted to INT_MAX32 to prevent negative
expire time values. (Bug #20478242, Bug #75790)
* InnoDB: Removal of a foreign key object from the data
dictionary cache during error handling caused the server
to exit. (Bug #20442523)
* InnoDB: SHOW ENGINE INNODB STATUS output showed negative
reservation and signal count values due to a counter
overflow error. (Bug #20417397)
* InnoDB: Failure to check the status of a cursor
transaction read-only option before reusing the cursor
transaction for a write operation resulted in a server
exit during a memcached workload. (Bug #20391552)
* InnoDB: MDL locks taken by memcached clients caused a
MySQL Enterprise Backup FLUSH TABLES WITH READ LOCK
operation to hang. (Bug #20275612)
* InnoDB: Estimates that were too low for the size of merge
chunks in the result sorting algorithm caused a server
exit. (Bug #20049521)
* InnoDB: For full-text searches, the optimizer could
choose an index that does not produce correct relevancy
rankings. (Bug #74686, Bug #19950568)
* Partitioning: When creating a partitioned table, using a
partition-level DATA DIRECTORY or INDEX DIRECTORY option
value containing an excessive number of characters was
handled incorrectly. (Bug #20809045)
* Partitioning: Executing an ALTER TABLE on a partitioned
table on which a write lock was in effect could cause
subsequent SQL statements on this table to fail. (Bug
#74288, Bug #74634, Bug #19784790, Bug #19918805)
References: See also Bug #19856162, Bug #74451.
* Replication: When binary logging was enabled, using
stored functions and triggers resulting in a long running
procedure that inserted many records caused the memory
use to increase rapidly. This was due to memory being
allocated per variable. The fix ensures that in such a
situation, memory is allocated once and the same memory
is reused. (Bug #75879, Bug #20531812)
* Replication: If an error was encountered while adding a
GTID to the received GTID set, the log lock was not being
correctly released. This could cause a deadlock. (Bug
#75781, Bug #20492319)
* Replication: A slave running MySQL 5.6.24 or earlier
could not connect to a master running MySQL 5.7.6 and
later that had gtid_mode=OFF_PERMISSIVE or
gtid_mode=ON_PERMISSIVE. The fix ensures that a slave
running MySQL 5.6.25 and later can connect to such a
master as long as the slave's gtid_mode is compatible. In
other words, a slave running MySQL 5.6.25 and later which
has gtid_mode=OFF can connect to a master running MySQL
5.7.6 and later which has gtid_mode=OFF_PERMISSIVE, and a
slave running MySQL 5.6.25 and later which has
gtid_mode=ON can connect to a master running MySQL 5.7.6
and later which has gtid_mode=ON_PERMISSIVE. Other
combinations are incompatible. (Bug #75769, Bug
#20471216)
* Replication: If an error occurred when using a
multi-threaded slave, issuing a CHANGE MASTER TO
statement which resulted in an
ER_MTS_CHANGE_MASTER_CANT_RUN_WITH_GAPS error, and then
issuing RESET SLAVE, made it impossible to change master
due to repeated ER_MTS_CHANGE_MASTER_CANT_RUN_WITH_GAPS
errors. Running the debug version of mysqld caused an
unexpected exit in this case. The fix ensures that the
recovery process for multi-threaded slaves avoids this.
(Bug #75574, Bug #20411374)
* Replication: When using semisynchronous replication
performance was degrading when the number of threads
increased beyond a certain threshold. To improve
performance, now only the thread which is committing is
responsible for deleting the active transaction node. All
other operations do not touch this active transaction
list. (Bug #75570, Bug #20574628)
* Replication: Using mysqlbinlog to process log events
greater than 1.6GB failed with an out of memory error.
This was caused by an internal error converting the
length variable. The fix upgrades the length variable to
avoid overflow in both encoding and decoding functions.
(Bug #74734, Bug #20350989)
* Replication: When master_info_repository=TABLE the
receiver thread stores received event information in a
table. The memory used in the process of updating the
table was not being freed correctly and this could lead
to an out of memory error. The fix ensures that after an
event is flushed to the relay log file by a receiver
thread, the memory used is freed. (Bug #72885, Bug
#19390463, Bug #69848, Bug #20124342)
* Replication: Using mysqlbinlog to replay a relay log
which ended with GTID_LOG_EVENT could cause the following
error:
ERROR 1790 (HY000) @@SESSION.GTID_NEXT cannot be changed
by a client that owns a GTID. The client owns UUID:GTID.
Ownership is released on COMMIT or ROLLBACK.
If a relay log rotate happens (either through a receiver
thread restart or after issuing the ROTATE command)
exactly after writing a GTID_LOG_EVENT, when replaying
such a relay log's end ROTATE_EVENT, it was mistakenly
identified as being inside a transaction, whereas the
transaction was actually started after GTID_LOG_EVENT.
This caused mysqlbinlog to append SET
@@SESSION.GTID_NEXT='AUTOMATIC', resulting in two
GTID_NEXT statements one after the other. The fix ensures
that mysqlbinlog generates SET
@@SESSION.GTID_NEXT='AUTOMATIC' only outside of a
transaction and when there has not been a previous
GTID_LOG_EVENT.
Similarly, using mysqlbinlog to concatenate and replay a
relay log which contained a partial GTID transaction
caused the above error. A relay log can contain a partial
GTID transaction when AUTO_POSITION is enabled if a
receiver thread is restarted when it is in the middle of
transferring a transaction from a master. On restart the
slave retrieves the full transaction again. In this case,
the first relay log contains a partial GTID transaction
and the second relay log contains the full GTID
transaction again. When using mysqlbinlog to concatenate
such a relay log, the partial transaction was not being
correctly detected and therefore a ROLLBACK was not being
correctly generated. The fix identifies partial GTID
transactions using the format description event of the
second relay log, ensuring that a ROLLBACK is correctly
added. (Bug #70711, Bug #17650326)
* For small values of the read_rnd_buffer_size system
variable, internal caching of temporary results could
fail and cause query execution failure. (Bug #20895852)
* The normalize_statement() UDF used by MySQL Enterprise
Firewall could cause a server exit for certain
password-related statements. (Bug #20873209)
* A failed FLUSH PRIVILEGES statement followed by
statements to create or drop accounts could cause a
server exit. (Bug #20857652)
* std::stringstream code used by MySQL Enterprise Firewall
could cause a server exit. (Bug #20848536)
* SHOW VARIABLES mutexes were being locked twice, resulting
in a server exit. (Bug #20788853)
* ull2dec() was modified to avoid a problem with GCC 5 in
optimized mode. (Bug #20768820)
* Using GCC 5, debug builds failed due to compiler
warnings. (Bug #20768717)
* A Provides rule in RPM .spec files misspelled
"mysql-embedded" as "mysql-emdedded". (Bug #20734434)
* The mysql_firewall_max_query_size system variable should
be read only at runtime, but it was possible to modify
it. (Bug #20608993)
* MySQL Enterprise Firewall could leak memory in the
unlikely event of failure to store information in an
INFORMATION_SCHEMA table. (Bug #20593257)
* Using a MySQL 5.6 version of mysqladmin to change the
password for an account on a MySQL 5.7.6 installation
resulted in an unusable account password. (Bug #20590548)
* AddressSanitizer compilation errors were silenced. (Bug
#20459338, Bug #75740, Bug #20459363)
* Under certain conditions, the libedit command-line
library could write outside an array boundary and cause a
client program crash. (Bug #20318154)
* mysql_config_editor could exit abnormally while
encrypting passwords. (Bug #20294225)
* Host value matching for the grant tables could fail to
use the most specific of values that contained wildcard
characters. (Bug #20181776)
* For MySQL distributions linked against yaSSL, a corrupt
client key file could cause clients to exit. (Bug
#20168526)
* For join queries with a large number of tables, the
server could exit converting the join to a semi-join.
(Bug #20109861)
* Deleting rows from mysql.user following by granting
privileges to a new account could result in a server
exit. (Bug #20031475)
* Renaming the mysql.procs_priv table and executing SHOW
GRANTS resulted in a server exit. (Bug #20006361)
* Within a stored procedure, access to view columns after
DDL or FLUSH TABLES statements in the procedure could
cause a server exit. (Bug #19897405)
* Execution of certain BINLOG statements while temporary
tables were open by HANDLER statements could cause a
server exit. (Bug #19894987)
* For a prepared statement with an ORDER BY that refers by
column number to a GROUP_CONCAT() expression that has an
outer reference, repeated statement execution could cause
a server exit. (Bug #19814337)
* CMake configuration was adjusted to handle new warnings
reported by Clang 3.5, using the
-Wpointer-bool-conversion and -Wundefined-bool-conversion
compiler options. (Bug #19584183)
* Loading corrupt spatial data into a MyISAM table could
cause the server to exit during index building. (Bug
#19573096)
* Specifying --general_log_file= (with an empty value) at
server startup caused the server to fail and exit. (Bug
#19392264)
* CMake configuration was adjusted to handle warnings
reported by Clang 3.3. (Bug #17486216)
* Some MySQL Enterprise Firewall diagnostic messages were
written outside the control of the log_error_verbosity
system variable. (Bug #76612, Bug #20848331)
* The server rejected empty COM_SHUTDOWN packets. (Bug
#76552, Bug #20810928)
References: This bug was introduced by Bug #14525642.
* Inappropriate -Werror options could appear in
mysql_config --cflags output. (Bug #76019, Bug #20590904)
* In the Performance Schema threads table, the
PROCESSLIST_STATE and PROCESSLIST_INFO values did not
change for the thread/sql/main main thread instrument as
the thread state changed. (Bug #74517, Bug #19887143)
* Certain queries for the INFORMATION_SCHEMA TABLES and
COLUMNS tables could lead to excessive memory use when
there were large numbers of empty InnoDB tables. (Bug
#72322, Bug #18592390)
* Queries that included a HAVING clause based on
nondeterministic functions could produce incorrect
results. (Bug #69638, Bug #17055185)
* For logging of prepared statements to the general query
log, the Execute line was logged after statement
execution, not before. (Bug #69453, Bug #16953758, Bug
#20536590)
* MySQL failed to compile using OpenSSL 0.9.8e. (Bug
#68999, Bug #16861371)
On Behalf of the MySQL RE team at Oracle
Hery Ramilison