Dear MySQL users,

MySQL Server 5.5.50 is a new version of the 5.5 production release
of the world's most popular open source database. MySQL 5.5.50 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:

http://dev.mysql.com/tech-resources/interviews/thomas-ulin-mysql-55.html

Documentation:

http://dev.mysql.com/doc/refman/5.5/en/mysql-nutshell.html

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.

http://mysql.com/products/enterprise/

For information on installing MySQL 5.5.50 on new servers, please see
the MySQL installation documentation at

http://dev.mysql.com/doc/refman/5.5/en/installing.html

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

http://dev.mysql.com/doc/refman/5.5/en/upgrading.html

MySQL Database 5.5.50 is available in source and binary form for a
number of platforms from our download pages at:

http://dev.mysql.com/downloads/mysql/

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:

http://dev.mysql.com/doc/relnotes/mysql/5.5/en/news-5-5-50.html

Enjoy!


==============================================================================

Changes in MySQL 5.5.50 (2016-06-02)


* Functionality Added or Changed

* Bugs Fixed

Functionality Added or Changed

* The version of the tcmalloc library included in MySQL
distributions was very old. It has been removed and is no
longer included with MySQL. (Bug #80994, Bug #23068660)

Bugs Fixed

* INSERT with ON DUPLICATE KEY UPDATE and REPLACE on a
table with a foreign key constraint defined failed with
an incorrect "duplicate entry" error rather than a
foreign key constraint violation error. (Bug #23135731)
References: This issue is a regression of: Bug #78853,
Bug #22037930.

* Setting sort_buffer_size to a very large value could
cause some operations to fail with an out-of-memory
error. (Bug #22594514)

* Several potential buffer overflow issues were corrected.
(Bug #21977380, Bug #23187436, Bug #23202778, Bug
#23195370, Bug #23202699)

* If the CA certificate as given to the --ssl-ca option had
an invalid path, yaSSL returned an error message
different from OpenSSL. Now both return SSL connection
error: SSL_CTX_set_default_verify_paths failed. (Bug
#21920657)

* Some string functions returned one or a combination of
their parameters as their result. If one of the
parameters had a non-ASCII character set, the result
string had the same character set, resulting in incorrect
behavior when an ASCII string was expected. (Bug
#18740222)

* A null pointer dereference of a parser structure could
occur during stored procedure name validation. (Bug
#79396, Bug #22286421)

* mysqld_multi displayed misleading error messages when it
was unable to execute my_print_defaults. (Bug #74636, Bug
#19920049)