オリジナル版：http://dev.mysql.com/doc/refman/5.5/en/news-5-5-29.html
MySQL 5.5.29は世界でもっともポピュラーなオープンソースデータベースの5.5のプロダクトリリースの新しいバージョンです。MySQL 5.5.29はプロダクションシステムでの使用をお勧めします。
MySQL 5.5は最新のマルチCPUやマルチコアハードウェアやオペレーティングシステムの利点を生かし、MySQLデータベースのパフォーマンスとスケーラビリ ティを改善するための影響の大きい変更をいくつか含んでいます。現在ではInnoDBがMySQLデータベースのデフォルトのストレージエンジンであり、 ACIDトランザクション、参照整合性、クラッシュリカバリをデフォルトで提供しています。
MySQL 5.5は以下の多くの新しい強化も含んでいます：
- Windowsにおける特有の機能と改善を利用した著しいパフォーマンス向上 - 新しい準同期レプリケーションとレプリケーションハートビートによるより高いレベルの可用性 - 改善されたインデックスとテーブルパーティショニング、SIGNAL/RESIGNALサポート、そして新しいPERFORMANCE_SCHEMAに含まれる強化された診断法による改善されたユーザビリティ
MySQL 5.5の新機能のより完全な概観については、以下のリソースを参照下さい。
MySQL 5.5 GA、Tomas Ulinのインタビュー:
http://dev.mysql.com/tech-resources/interviews/thomas-ulin-mysql-55.html
ドキュメント:
http://dev.mysql.com/doc/refman/5.5/en/mysql-nutshell.html
ホワイトペーパー: MySQL 5.5の新機能
http://dev.mysql.com/doc/refman/5.5/en/mysql-nutshell.html
製品レベルのシステムでMySQLを稼動させているならば、MySQL製品、バックアップ、モニタリング、モデリング、開発、管理ツールの包括的なセット を含むMySQLパフォーマンス、セキュリティ、アップタイムの高いレベルを実現するMySQL Enterprise Editionの製品詳細に注目してください。
http://mysql.com/products/enterprise/
新しいサーバへMySQL 5.5.29をインストールする情報として、以下のMySQLのインストールドキュメントを参照してください。
http://dev.mysql.com/doc/refman/5.5/en/installing.html
前回のMySQLリリースからアップグレードするには、以下のアップグレードについての注意事項を参照してください。
http://dev.mysql.com/doc/refman/5.5/en/upgrading-from-previous-series.html
MySQL Server 5.5.29は、http://dev.mysql.com/downloads/とミラーサイトのダウンロード・ページから、ソースコード及び多くのプラットフォームのためのバイナリで現在利用可能です。
次の節では、MySQL 5.5の以前のバージョンからの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できます。
http://dev.mysql.com/doc/refman/5.5/en/news-5-5-29.html
Changes in MySQL 5.5.29 (21-December-2012)
Functionality Added or Changed
* The SHOW AUTHORS and SHOW CONTRIBUTORS statements are now
deprecated in MySQL 5.5 and have been removed in MySQL 5.6.
Bugs Fixed
* Performance: InnoDB: The timing values for low-level InnoDB
read operations were adjusted for better performance with fast
storage devices, such as SSD
(http://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_ssd
). This enhancement primarily affects read operations for BLOB
columns in compressed
(http://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_com
pression) tables. (Bug #13702112, Bug #64258)
* Important Change: InnoDB: A DML
(http://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_dml
) statement using the index merge access method could lock
many rows from the table, even when those rows were not part
of the final result set. This fix reduces the excessive
locking
(http://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_loc
king) by releasing the locks of unmatched rows. This
optimization affects only transactions with isolation level
equal to or less strict than READ COMMITTED; it does not apply
to transactions using REPEATABLE READ or SERIALIZABLE
isolation level. (Bug #14226171)
* InnoDB: An online DDL operation for an InnoDB table
incorrectly reported an empty value ('') instead of the
correct key value when it reported a duplicate key error for a
unique index using an index prefix. (Bug #14729221)
* InnoDB: If a CREATE TABLE statement failed due to a disk full
error, some memory allocated during the operation was not
freed properly. (Bug #14708715)
* InnoDB: With the innodb_file_per_table setting enabled, a DROP
TABLE operation could cause a crash, due to a race condition
that depended on the timing of pending I/O requests. (Bug
#14594600, Bug #66718)
* InnoDB: If the server crashed at the specific point when a
change buffer
(http://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_cha
nge_buffer) entry was being merged into a buffer pool page,
the transaction log and the change buffer were left in an
inconsistent state. After a restart, MySQL could crash after
reading the corresponding secondary index page. The problem
was more likely to occur in MySQL 5.5 or later, where the
original insert buffering
(http://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_ins
ert_buffering) mechanism was generalized to cover other
operations. (Bug #14636528, Bug #66819, Bug #58571, Bug
#61104, Bug #65443)
* InnoDB: Inserting data of varying record lengths into an
InnoDB table that used compression
(http://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_com
pression) could cause the server to halt with an error. (Bug
#14554000, Bug #13523839, Bug #63815, Bug #12845774, Bug
#61456, Bug #12595091, Bug #61208)
* InnoDB: If a table was defined with an index key length very
close to the upper length limit of 3072, a query against that
table could cause a serious error. (Bug #14500557, Bug #66413)
* InnoDB: When an auto-increment column used a FLOAT or DOUBLE
data type, if the auto-increment value became very large
(larger than the maximum unsigned long long value), subsequent
inserts could fail or cause the server to halt. (Bug
#14145950, Bug #55071)
* InnoDB: If a transaction was started with a consistent
snapshot, then new indexes were added to the table while the
transaction was in progress, a subsequent UPDATE statement
could incorrectly encounter the error:
HA_ERR_TABLE_DEF_CHANGED: insufficient history for index
This issue could cause an assertion error in debug builds.
(Bug #14036214)
* InnoDB: The error message was improved for the case where an
UPDATE failed because the row included several BLOB values
greater than 768 bytes each, causing the size of a row to
exceed half the page size
(http://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_pag
e_size). The old message, was misleading; it suggested using
BLOBs, when the 768-byte prefix for each BLOB column was the
cause of the limit error:
Error Code 1118: Row size too large. The maximum row size for
the used table type, not counting BLOBs, is 8126. You have to
change some columns to TEXT or BLOBs
A workaround for the problem was to create the table with the
ROW_FORMAT=DYNAMIC or ROW_FORMAT=COMPRESSED clause, which is
now suggested in the message. (Bug #13453036, Bug #63507)
* InnoDB: In rare circumstances, MySQL could apply InnoDB undo
(http://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_und
o) records out of order during a ROLLBACK
(http://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_rol
lback) of an operation that modified a BLOB column. This issue
could cause an assertion error in debug builds:
!bpage->file_page_was_freed
(Bug #13249921)
* Replication: Updates writing user variables whose values were
never set on a slave while using --replicate-ignore-table
could cause the slave to fail. (Bug #14597605)
References: This bug was introduced by Bug #14275000.
* Replication: Backtick (`) characters were not always handled
correctly in internally generated SQL statements, which could
sometimes lead to errors on the slave. (Bug #14548159)
* Replication: Following an insert into a nontransactional table
that failed due to insufficient disk space, the server did not
properly clean up all pending events, leading to an assert or
possibly to other errors. (Bug #11750014)
* Very long database names in queries could cause the server to
exit. (Bug #15912213)
* Within a stored procedure, executing a multiple-table DELETE
statement that used a very long table alias could cause the
server to exit. (Bug #15954896)
* Very long table aliases in queries could cause the server to
exit. (Bug #15948123)
* Attempting to create an auto-increment
(http://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_aut
o_increment) column in an InnoDB table with a NULL type
attribute could cause a serious error. (Bug #14758479)
* A DELETE statement for an InnoDB table could write incorrect
transaction metadata into a record, causing the server to halt
with an error. To work around this issue, reduce the specified
length of the primary key to less than 1K bytes. (Bug
#14731482)
* Repeated execution of a query containing a subquery that used
MAX() could result in increasing memory consumption. (Bug
#14683676)
* USE dbname could fail with Unknown database when dbname
contained multiple backtick (`) characters. (Bug #14645196)
* The configure.pl script that converts GNU configure options to
CMake equivalents generated erroneous output for the
--with-client-ldflags and --with-mysqld-ldflags options. It
now ignores those options. (Bug #14593123)
* SHOW PROFILE could be used to cause excessive server memory
consumption. (Bug #14629232)
* The thread cache implementation worked in LIFO rather than
FIFO fashion and could result in a thread being denied service
(although this was a remote possibility). (Bug #14621627)
* Within a stored program, memory allocated to hold condition
information was not released until program exit, leading to
excessive memory use. (Bug #14640599)
* Improper memory cleanup could cause the server to exit. (Bug
#14536113)
* Granting or revoking the PROXY privilege caused the server to
exit if the server was started with --skip-name-resolve. (Bug
#14211140)
* CREATE USER and DROP USER could fail to flush the privileges,
requiring FLUSH PRIVILEGES to be used explicitly. (Bug
#13864642)
* Access to INFORMATION_SCHEMA tables through a view could leak
memory. (Bug #13734987)
* A memory leak could occur for queries containing a subquery
that used GROUP BY on an outer column. (Bug #13724099)
* On Microsoft Windows with CMake 2.6, the build process would
not stop if the create_initial_db step failed. (Bug #13713525)
* The test in mysqld_safe for the presence of the --plugin_dir
option and assignment of a default value to it were performed
before the actual argument parsing took place. (Bug #13548161)
* CHECK TABLE and REPAIR TABLE could crash if a MyISAM table had
a corrupt key (.MYI) file. Now the server produces an error.
(Bug #13556441)
* Improper memory cleanup could cause the server to exit. (Bug
#13340270)
* A memory leak occurred due to failure to clean up after
QUICK_INDEX_MERGE_SELECT/Unique. (Bug #12694872, Bug
#14542543)
* The number of connection errors from a given host as counted
by the server was periodically reset, with the result that
max_connect_errors was never reached and invalid hosts were
never blocked from trying to connect. (Bug #11753779)
References: See also Bug #38247, Bug #43006, Bug #45584, Bug
#45606.
* During optimization, ZEROFILL values may be converted to
string constants. However, CASE expressions did not handle
switching data types after the planning stage, leading to CASE
finding a null pointer instead of its argument. (Bug #57135,
Bug #11764313)
* In debug builds, an InnoDB assertion was overly aggressive
about prohibiting an open range. (Bug #66513, Bug #14547952)
* On Windows, the Perl version of mysql_install_db created
system tables in the mysql database that were not populated
properly. (Bug #65584, Bug #14181049)
* mysqld_safe ignored the value of the UMASK environment
variable, leading to behavior different from mysqld with
respect to the access mode of created files. Now mysqld_safe
(and mysqld_multi) attempt to approximate the same behavior as
mysqld. (Bug #57406, Bug #11764559)
* LAST_INSERT_ID(expr) did not work for expr values greater than
the largest signed BIGINT value. (Bug #20964, Bug #11745891)