MySQL Community Server 5.5.40 がリリースされました

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 5.5.40がリリースされました。

MySQL Server 5.5.40 is a new version of the 5.5 production release
of the world's most popular open source database. MySQL 5.5.40 is
recommended for use on production systems.

MySQL 5.5 includes several high-impact enhancements to improve the
performance and scalability of the MySQL Database, taking advantage of
the latest multi-CPU and multi-core hardware and operating systems. In
addition, with release 5.5, InnoDB is now the default storage engine for
the MySQL Database, delivering ACID transactions, referential integrity
and crash recovery by default.

MySQL 5.5 also provides a number of additional enhancements including:

      - Significantly improved performance on Windows, with various
        Windows specific features and improvements
      - Higher availability, with new semi-synchronous replication and
        Replication Heartbeat
      - Improved usability, with Improved index and table partitioning,
        SIGNAL/RESIGNAL support and enhanced diagnostics, including a new
        Performance Schema monitoring capability.

For a more complete look at what's new in MySQL 5.5, please see the
following resources:

MySQL 5.5 is GA, Interview with Tomas Ulin:


Whitepaper: What's New in MySQL 5.5:

If you are running a MySQL production level system, we would like to
direct your attention to MySQL Enterprise Edition, which includes the
most comprehensive set of MySQL production, backup, monitoring,
modeling, development, and administration tools so businesses can
achieve the highest levels of MySQL performance, security and uptime.

For information on installing MySQL 5.5.40 on new servers, please see
the MySQL installation documentation at

For upgrading from previous MySQL releases, please see the important
upgrade considerations at:

MySQL Database 5.5.40 is available in source and binary form for a
number of platforms from our download pages at:

The following section lists the changes in the MySQL source code since
the previous released version of MySQL 5.5. It may also be viewed
online at:


Changes in MySQL 5.5.40 (2014-09-22)

    Bugs Fixed

      * InnoDB: An ALTER TABLE ... ADD FOREIGN KEY operation could
        cause a serious error. (Bug #19471516, Bug #73650)

      * InnoDB: With a transaction isolation level less than or equal
        to READ COMMITTED, gap locks were not taken when scanning a
        unique secondary index to check for duplicates. As a result,
        duplicate check logic failed allowing duplicate key values in
        the unique secondary index. (Bug #19140907)
        References: This bug is a regression of Bug #16133801.

      * InnoDB: During recovery, a segmentation fault would occur when
        marking a table as corrupt. (Bug #18942294)

      * yaSSL client code did not validate the encryption size or
        session ID length, which could cause the client to exit. (Bug
        #19463277, Bug #19463565)

      * MySQL installation from RPM packages could fail if Postfix had
        been installed using yum. (Bug #19392127)

      * yaSSL could fail preauthorization if the client supplied
        inaccurate buffer lengths. (Bug #19370676, Bug #19355577)

      * Competition between threads could lead to timeout failure
        trying to rotate the audit log file. (Bug #19184973)

      * On Linux (OEL6), if Sun DTrace was installed, the MySQL build
        failed. (Bug #19149091)

      * LPAD() and RPAD() could cause a server exit if the pad string
        argument was not well formed. (Bug #18935421)

      * The optimizer could create a zero-length column for a
        temporary table, causing a server exit. (Bug #18928848)

      * MOD for very small decimal right-hand arguments could cause a
        server exit. (Bug #18469276)

      * The client library now includes a call to
        X509_verify_cert_error_string() in the SSL certificate
        verification code, to be more robust in detecting invalid
        certificates. (Bug #18384260)

      * The thread_concurrency system variable is deprecated, but no
        warning resulted from setting it at server startup. (Bug

      * Sending a SIGQUIT or SIGINT signal to mysql could result in a
        glibc double free or corruption error. (Bug #17297324)

      * LIKE matches failed for code points of HALF WIDTH KATAKANA in
        the sjis and cp932 character sets. (Bug #47641, Bug #11755818)

      * On EL7, installation of MySQL from RPM packages could fail if
        postfix had previously been installed using yum. (Bug #73507,
        Bug #19392051, Bug #19392149)

      * mysql_upgrade could fail if the mysql.user table contained
        multiple accounts with the same user name and host name where
        the host name differed in lettercase. This is still not
        permitted, but now mysql_upgrade prints a more informative
        error message to indicate the nature of the problem:
        ERROR 1644 (45000): Multiple accounts exist for user_name, host_name
        that differ only in Host lettercase; remove all except one of them
        (Bug #72066, Bug #18415196)

      * If the general query log or slow query log file was set to a
        FIFO or socket file, and the file reader went away, the server
        stopped executing statements. Now the server detects such
        files, logs an error message, and continues with the
        appropriate log disabled. (Bug #67088, Bug #14757009)