Dear MySQL users,

MySQL Server 5.6.36, a new version of the popular Open Source
Database Management System, has been released. MySQL 5.6.36 is
recommended for use on production systems.

For an overview of what's new in MySQL 5.6, please see

http://dev.mysql.com/doc/refman/5.6/en/mysql-nutshell.html

Starting with 5.6.11, Microsoft Windows packages for MySQL 5.6
are available both as a "full" installer and as a "web" installer.
The full installer is significantly larger and comes bundled with
the latest software releases available. This bundle makes it easy
to download and configure a full server and development suite.

The web installer doesn't come bundled with any actual products
and instead relies on download-on-demand to fetch only the
products you choose to install. This makes the initial download
much smaller but increases install time as the individual products
will need to be downloaded.

For information on installing MySQL 5.6.36 on new servers or upgrading
to MySQL 5.6.36 from previous MySQL releases, please see

http://dev.mysql.com/doc/refman/5.6/en/installing.html

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

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

Not all mirror sites may be up to date at this point in time, so if you
can't find this version on some mirror, please try again later or choose
another download site.

We welcome and appreciate your feedback, bug reports, bug fixes,
patches, etc:

https://wikis.oracle.com/display/mysql/Contributing

The following section lists the changes in the MySQL 5.6 since
the release of MySQL 5.6.35. It may also be viewed
online at

http://dev.mysql.com/doc/relnotes/mysql/5.6/en/news-5-6-36.html

Enjoy!


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

Changes in MySQL 5.6.36 (2017-04-10, General Availability)


* Compilation Notes

* Configuration Notes

* Packaging Notes

* Security Notes

* Thread Pool Notes

* Functionality Added or Changed

* Bugs Fixed

Compilation Notes

* Windows builds now use the default runtime libraries
(builds use the /MD flag). (Bug #25611609)

* CMake support was added for compiling with Developer
Studio 12.6. (Bug #25384295)

Configuration Notes

* MySQL failed to compile if -DENABLE_DEBUG_SYNC=OFF AND
-DWITH_DEBUG=ON were both given. The ENABLE_DEBUG_SYNC
option has been removed and enabling WITH_DEBUG enables
Debug Sync. (Bug #18374703)

Packaging Notes

* Changes in RPM package structure require a larger set of
packages to be removed to install MySQL Server cleanly.
(Bug #25603087)

* To avoid potential race conditions, Debian packages now
use the GNU install utility rather than a combination of
mkdir, touch, and chown. (Bug #25258829)

* CMake-generated packaging for Debian/Ubuntu packages was
refactored for improved maintainability. The change
includes updated logic for correctly replacing native
distribution packaging in Debian and Ubuntu. (Bug
#25126961, Bug #25251872, Bug #84198)

* Reminder: MySQL 5.6 requires the Microsoft Visual C++
2010 Redistributable Package to run on Windows platforms.
Users should make sure the package has been installed on
the system before starting the server. The package is
available at the Microsoft Download Center
(http://www.microsoft.com/en-us/download/default.aspx).

Security Notes

* The linked OpenSSL library for the MySQL Commercial
Server has been updated to version 1.0.2k. For a
description of issues fixed in this version, see
http://www.openssl.org/news/vulnerabilities.html.
This change does not affect the Oracle-produced MySQL
Community build of MySQL Server, which uses the yaSSL
library instead. (Bug #25768671)

* The mysql_options() C API function now supports a
MYSQL_OPT_SSL_MODE option. The only permitted option
value is SSL_MODE_REQUIRED, to require a secure
connection to the server. It causes mysql_real_connect()
to fail if an encrypted connection cannot be obtained,
without falling back to an unencrypted connection. Thus,
mysql_real_connect() returns an error if the server does
not support SSL or the client is not configured to use
SSL. The client/server exchange terminates immediately
after the initial server packet has been received if the
server indicates that it does not support SSL.
To require an encrypted connection in MySQL 5.6, the
standard MySQL client programs call mysql_options() to
set MYSQL_OPT_SSL_MODE if the --ssl-mode=REQUIRED
command-line option was specified. Third-party
applications that must be able to require encrypted
connections can use the same technique. For details, see
mysql_ssl_set()
(http://dev.mysql.com/doc/refman/5.6/en/mysql-ssl-set.html).
The minor C API version number was not incremented for
this change. Application programs compiled for MySQL 5.6
that require MYSQL_OPT_SSL_MODE may fail to operate
properly if the dynamic loader provides an older client
library without MYSQL_OPT_SSL_MODE. Such applications
must be written to handle this possibility by checking
whether the mysql_options() call succeeds or fails. (Bug
#25575605)

Thread Pool Notes

* To improve thread_pool plugin performance, connection
authentication and initialization have been moved from
the acceptor thread to the thread pool worker threads
that handle client connections. This enables the acceptor
thread to handle new connections at a higher rate with
reduced latency. The INFORMATION_SCHEMA
TP_THREAD_GROUP_STATE table now contains a
CONNECT_THREAD_COUNT column that indicates the number of
threads that are processing or waiting to process
connection initialization and authentication. There can
be a maximum of four connection threads per thread group;
these threads expire after a period of inactivity. (Bug
#17159742)

Functionality Added or Changed

* The performance of UTF-8 binary collations was improved.
(Bug #24788778, Bug #83247, Bug #25076862)

* Consistency and maintainability of Debian/Ubuntu
packaging maintainer scripts was improved. (Bug
#23588977)

* mysql_secure_installation is more strict about what it
considers valid yes and no responses. (Bug #13344753, Bug
#62925)

Bugs Fixed

* InnoDB: The restriction that required the first undo
tablespace to use space ID 1 was removed. The first undo
tablespace may now be assigned a space ID other than 1.
Space ID values for undo tablespaces are still assigned
in a consecutive sequence. (Bug #25551311)

* InnoDB: Compiling the server without the Performance
Schema caused a build failure. (Bug #25348787)

* InnoDB: The file handle type name for InnoDB file I/O
Performance Schema instrumentation was changed from
os_pfs_file_t to pfs_os_file_t. (Bug #25220118)

* InnoDB: A server exit on restart was caused by missing
my_thread_init() and my_thread_exit() functions for
background threads that initialize the st_my_thread_var
structure. (Bug #25167032)

* InnoDB: A memcached read operation with a non-default
read batch size configuration resulted in a server exit.
(Bug #25147515)

* InnoDB: Performance Schema instrumentation for InnoDB
file I/O was disabled on Windows. (Bug #14025581)

* InnoDB: The row_search_mvcc() function unnecessarily
traversed the entire table for a range query, which
occurred when the record was not in the transaction read
view. (Bug #84202, Bug #23481444, Bug #25251375)

* Replication: When using a multi-threaded slave
(slave_parallel_workers greater than 0) the value of
Seconds_Behind_Master was incorrect when rotating a relay
log. (Bug #23532304)

* mysqldump failed to properly quote certain identifiers in
SQL statements written to the dump output. (Bug
#25717383)

* Client preauthorization by the server was missing a
length check for a length-encoded string. (Bug #25714674)

* For Debian/Ubuntu packages, user-defined collation files
could be overwritten during MySQL upgrades. Charset files
are now marked as conffiles so that user customizations
generate a prompt during upgrades whether to overwrite
them. (Bug #25525628, Bug #84761)

* For CREATE TABLE statements that specified the table name
with a database qualifier and included a DATA DIRECTORY
or INDEX DIRECTORY option, an error occurred if there was
no default database. (Bug #25514146, Bug #84861)

* Starting the server with
performance_schema_digests_size=1 caused an abnormal
exit. (Bug #25492129, Bug #84786)

* mysqld_safe did not check whether the directory named by
the --basedir option existed. (Bug #25365194)

* mysqld_safe failed if the error log file named by the
--log-error option was a FIFO. (Bug #25356221, Bug
#84427)

* mysqld_safe could fail if the --datadir option value
ended with a / character. (Bug #25319457)

* A recent change to mysqld_safe caused the mysql.server
script to be unable to start it if the base directory was
specified as an absolute path that differed from the
compiled-in default absolute path. (Bug #25319392, Bug
#84263)

* The fix for Bug #78777 had different effects depending on
whether the Performance Schema is enabled. (Bug
#25309017, Bug #84305)
References: This issue is a regression of: Bug #78777.

* The connection_control plugin failed to compile if the
Performance Schema was disabled. (Bug #25308357, Bug
#84304)

* For System V init scripts for RPMs, the [mysqld]
option-file section was being ignored for some options,
such as pid-file. (Bug #25287707, Bug #84172)

* Init scripts failed to launch mysqld_safe if a
non-default base directory was used. (Bug #25261472, Bug
#84219)

* mysqld_safe --no-defaults did not work (inadvertent
consequence of an earlier bug fix). (Bug #25244898, Bug
#84173)

* Semicolon (;) characters within or between statements
could cause distinct digests to be generated from
identical statements. (Bug #25244533, Bug #83253)

* For a client linked against libmysqlclient, invalid
memory access could occur during use of prepared
statements. (Bug #25164932)

* The fix for Bug #25088048 caused the command used by
mysqld_safe to start the MySQL server to no longer
include the mysqld path. (Bug #25144379)
References: This issue is a regression of: Bug #25088048.

* Executing a stored procedure containing a query that
accessed a view could allocate memory that was not freed
until the session ended. (Bug #25053286)

* A query could produce incorrect results if the WHERE
clause contained a dependent subquery, the table had a
secondary index on the columns in the select list
followed by the columns in the subquery, and GROUP BY or
DISTINCT permitted the query to use a Loose Index Scan.
(Bug #24671968, Bug #83005)

* Creation of a MyISAM temporary table during query
processing could fail if the key length in the query was
greater than the maximum MyISAM key length, resulting in
a server exit. (Bug #24659861)

* The DebugPrintTest and DebugPrintDeathTest unit tests did
not handle divide-by-zero testing properly on the Aarch64
platform. Thanks to Alexey Kopytov for the patch. (Bug
#24624555, Bug #82889)

* Changes made to mysqld_safe in recent MySQL releases
require the --ledir, --mysqld, --mysqld-version options
to be specified on the command line; they can no longer
be specified in option files. This could cause failure of
init scripts that invoke mysqld_safe. Such scripts now
pass the value of the MYSQLD_OPTS environment variable as
the first command-line argument to mysqld_safe, with the
value set to such command line-only mysqld_safe option
values as may be required. On platforms that use
/etc/sysconfig/mysqld, the MYSQLD_OPTS value can be set
in that file with a line such as this:
MYSQLD_OPTS=" --ledir=/mysqld_ledir --mysqld=my_wrapper "

The value of MYSQLD_OPTS can also include mysqld options
for mysqld_safe to pass to mysqld. (Bug #24619033, Bug
#82920)
References: This issue is a regression of: Bug #24464380,
Bug #24483092, Bug #25088048, Bug #25378439, Bug
#25378565.

* For LOAD DATA used to insert data into an updateable
view, the check to verify whether a column is actually
updatable was missing. (Bug #24595937)

* On Debian/Ubuntu platforms, the systemd startup script
for MySQL ignored datadir settings in /etc/mysql/my.cnf.
(Bug #24517024, Bug #82709)

* A regular expression pattern match into a large string
could result in a server exit due to memory allocation
failure or integer overflow. (Bug #24449076, Bug
#24449090)

* An incorrect error was reported for CREATE TABLE
statements with a large value for the CONNECTION table
option. The value is now limited to 1024 bytes. (Bug
#24437124)

* MySQL now uses readdir() rather than readdir_r(). The
latter has been deprecated since glibc 2.24 and caused
debug builds of MySQL and builds using GCC 6.1 to fail.
Additionally, several problems resulting in GCC 6.1
compiler warnings were corrected. (Bug #23708395, Bug
#24437737, Bug #82515, Bug #24459890, Bug #25103242)

* The -DWITH_EDITLINE=system CMake option failed with
recent versions of the editline library. (Bug #23708332,
Bug #25391997, Bug #84501)

* Grant tables with incorrect structure may cause problems
in user management operations. As a consequence of the
fix for this, for any operation that modifies a grant
table, the server now checks whether the table has the
expected structure and produces an error if not.
mysql_upgrade must be run to update the tables to the
expected structure. (Bug #23295423, Bug #25095876, Bug
#25448037)

* The QUOTE() function could allocate excessive memory. A
limit of max_allowed_packet bytes is now imposed and
returns NULL with a warning for attempts to allocate
more. (Bug #23195404)

* When attempting to locate the data directory, mysqld_safe
incorrectly considered $MY_BASEDIR_VERSION/var as one of
the possible locations. (Bug #23013510, Bug #80866)

* The main.log_tables-big test case could be unstable on
highly loaded hosts. Thanks to Laurynas Biveinis for the
patch. (Bug #22874167, Bug #80607)

* Queries that used an aggregate function with DISTINCT
could produce incorrect results. (Bug #22686994, Bug
#80310)

* With the use_index_extensions flag of the
optimizer_switch system variable disabled, some SELECT
DISTINCT queries could return incorrect results. (Bug
#21749123, Bug #78244)

* Debian packages were missing an AppArmor-related include
file and incorrectly were marked dependent on AppArmor
(making it impossible to disable AppArmor by uninstalling
it). (Bug #20768958)

* In a replication environment, SET PASSWORD or ALTER USER
could fail to execute on the slave due to failure to
parse the hash string correctly. (Bug #20228478)

* On non-Linux Unix systems, the mysql.server startup
script used the Linux command pidof rather than pgrep.
(Bug #13788154, Bug #64342)

* Starting multiple instances of mysqld_safe after an
abnormal server exit could result in one mysqld_safe
instance killing another. As a consequence of the bug
fix, the mysqld_safe.pid file is no longer used. (Bug
#11751149, Bug #41908)

* The --help message for mysqld_safe was corrected to
mention that the --no-defaults, --defaults-file, and
--defaults-extra-file options, if given, must be the
first argument. (Bug #11745176, Bug #11192)

* The bounds check for the XML parser position stack for
each level (which has a fixed depth) used the size of the
array as the upper limit, and so was off by one. This is
fixed by decreasing the allowable depth by one, which
actually matches the maximum number of elements in the
position stack. (Bug #83871, Bug #25111907)
References: See also: Bug #14040071, Bug #15948580.

* Timestamps for server-side prepared statements could be
written to the binary log up to a second behind
timestamps for the corresponding nonprepared statements,
leading to time value differences between master and
slave servers. (Bug #74550, Bug #19894382, Bug #25187670)