オリジナル版：http://dev.mysql.com/doc/refman/5.1/en/news-5-1-68.html
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 5.1.68がリリースされました。MySQL 5.1.68は、プロダクションシステムでの使用をお勧めします。
MySQL 5.1の新機能の概要については、以下を参照してください。
http://dev.mysql.com/doc/refman/5.1/en/mysql-nutshell.html
新たなサーバにMySQL 5.1.68をインストール、または以前のMySQLリリースからMySQL 5.1.61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/5.1/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。
http://forge.mysql.com/wiki/Contributing
MySQL 5.1に関するオープンな問題の情報については、以下のエラッタリストを参照してください。
http://dev.mysql.com/doc/refman/5.1/en/open-bugs.html
以下のセクションは、MySQL5.1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/refman/5.1/en/news-5-1-65.html
以下は、追加または変更された機能です。
Changes in MySQL 5.1.68 (5 February, 2013)
Bugs Fixed
* Performance: InnoDB: Optimized read operations for compressed
(http://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_com
pression) tables by skipping redundant tests. The check for
whether any related changes needed to be merged from the
insert buffer
(http://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_ins
ert_buffer) was being called more often than necessary. (Bug
#14329288, Bug #65886)
* Performance: InnoDB: Immediately after a table was created,
queries against it would not use loose index scans
(http://dev.mysql.com/doc/refman/5.1/en/group-by-optimization.
html#loose-index-scan). The issue went away following an ALTER
TABLE on the table. The fix improves the accuracy of the index
statistics
(http://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_ind
ex_statistics) gathered when the table is first created. (Bug
#14200010)
* Partitioning: InnoDB: Previously, when attempting to optimize
one or more partitions of a partitioned table that used a
storage engine that does not support partition-level OPTIMIZE,
such as InnoDB, MySQL reported Table does not support
optimize, doing recreate + analyze instead, then re-created
the entire table, but did not actually analyze it. Now in such
cases, the warning message is, Table does not support optimize
on partitions. All partitions will be rebuilt and analyzed. In
addition, the entire table is analyzed after first being
rebuilt. (Bug #11751825)
* InnoDB: The status variable
Innodb_buffer_pool_read_ahead_evicted could show an inaccurate
value, higher than expected, because some pages in the buffer
pool
(http://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_buf
fer_pool) were incorrectly considered as being brought in by
read-ahead
(http://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_rea
d_ahead) requests. (Bug #15859402, Bug #67476)
* InnoDB: Creating an index on a CHAR column could fail for a
table with a character set with varying length, such as UTF-8,
if the table was created with the ROW_FORMAT=REDUNDANT clause.
(Bug #15874001)
* InnoDB: If the server crashed at a precise moment during an
ALTER TABLE operation that rebuilt the clustered index
(http://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_clu
stered_index) for an InnoDB table, the original table could be
inaccessible afterward. An example of such an operation is
ALTER TABLE ... ADD PRIMARY KEY The fix preserves the original
table if the server halts during this operation. You might
still need to rename the .ibd file manually to restore the
original table contents: in MySQL 5.6 and higher, rename from
#sql-ib$new_table_id.ibd to table_name.ibd within the database
directory; prior to MySQL 5.6, the temporary file to rename is
table_name#1 or #2. (Bug #14669848)
* InnoDB: An error at the filesystem level, such as too many
open files, could cause an unhandled error during an ALTER
TABLE operation. The error could be accompanied by Valgrind
warnings, and by this assertion message:
Assertion `! is_set()' failed.
mysqld got signal 6 ;
(Bug #14628410, Bug #16000909)
* InnoDB: During shutdown, with the innodb_purge_threads
configuration option set greater than 1, the server could halt
prematurely with this error:
mysqld got signal 11
A workaround was to increase innodb_log_file_size and set
innodb_purge_threads=1. The fix was backported to MySQL 5.5
and 5.1, although those versions do not have the
innodb_purge_threads configuration option so the error was
unlikely to occur. (Bug #14234028)
* InnoDB: The value of the innodb_version variable was not
updated consistently for all server releases for the InnoDB
Plugin in MySQL 5.1, and the integrated InnoDB component in
MySQL 5.5, 5.6, and higher. Since InnoDB and MySQL Server
development cycles are fully integrated and synchronized, now
the value returned by the innodb_version variable is the same
as for the version variable. (Bug #13463493, Bug #63435)
* Partitioning: When used with a table having multiple columns
in its primary key, but partitioned by KEY using a column that
was not part of the primary key as the partitioning column, a
query using an aggregate function and DISTINCT such as SELECT
SUM(DISTINCT pk_column_1) FROM table WHERE pk_column_2 =
constant was not handled correctly. (Bug #14845133)
References: See also Bug #14495351. This bug was introduced by
Bug #13025132.
* Replication: Repeated execution of CHANGE MASTER TO statements
using invalid MASTER_LOG_POS values could lead to errors and
possibly a crash on the slave. Now in such cases, the
statement fails with a clear error message. (Bug #11764602,
Bug #57454)
* Replication: If the disk becomes full while writing to the
binary log, the server hangs until space is freed up manually.
It was possible after was done for the MySQL server to fail,
due to an internal status value being set when not needed. Now
in such cases, rather than trying to set this status, a
warning is written in the error log instead. (Bug #11753923,
Bug #45449)
* Microsoft Windows: Dynamic file names (with colons) are no
longer allowed. Static file names using the Alternate Data
Stream (ADS) NTFS functionality of Microsoft Windows may
continue to be used. (Bug #11761752)
* It was possible in theory for UpdateXML() to return NULL
incorrectly. (Bug #15948580)
References: See also Bug #13007062.
* For MEMORY tables with HASH indexes, DELETE sometimes failed
to delete all applicable rows. (Bug #51763, Bug #11759445)