MariaDB 10.2 Changes & Improvements

MariaDB 10.2 is no longer maintained. Please use a more recent release.

The most recent release of MariaDB 10.2 is:MariaDB 10.2.44 Stable (GA) Download Now

MariaDB 10.2 is a previous major stable version. The first stable release was in May 2017.

For details on upgrading from MariaDB 10.1, see .

The following lists the major new features in MariaDB 10.2:

Implemented Features

InnoDB as Default

• is now the default storage engine. Until , MariaDB used the XtraDB storage engine as default. XtraDB in 10.2 is not up to date with the latest features of InnoDB and cannot be used. As the InnoDB on disk format is identical to XtraDB's this will not cause any problems when upgrading to . See

Syntax / General Features

• storage engine added. (It has its own . In , it is considered Gamma) ()

• have been introduced.

• The statement was introduced

• New options for limiting resource usage and tls/ssl

Incompatible Changes

• has been split into a separate package, mariadb-plugin-tokudb.

• has been changed; in particular, NOT NULL fields with no default will no longer fall back to a dummy value for inserts which do not specify a value for that field.

• Replication from legacy MySQL servers may require setting to NONE.

• New : OVER, RECURSIVE, and ROWS.

Triggers

• Multiple for the same event ()

• The FOLLOWS/PRECEDES clauses have been added to the statement

• Multiple triggers are now counted in the Executed_triggers status variable ()

• and now include the date and time the trigger was created

Replication / Binary Log

• DML_only can rollback instances/databases/tables to an old snapshot ()

• New variable permits restricting the speed at which the slave reads the binlog from the master () — Original code from Tencent Game DBA Team, developed by chouryzhou.

• is supported () — Backported from MySQL 5.6 by Kristian Nielsen funded by Booking.com.

• is supported (

GeoJSON / JSON

• The (an alias for LONGTEXT) was introduced.

• added ()

• Implement and functions so the spatial features can be imported/exported using GeoJSON format ()

Information Schema

• An information schema plugin to report all user variables, which creates the ()

• Changes to the table. Literals are now quoted in the COLUMN_DEFAULT column to distinguish them from expressions (), and two new columns added providing information about columns ().

EXPLAIN

• now shows outer_ref_condition field which contains the condition that the(?) SELECT checks on each re-execution ()

• now shows sort_key field which shows the sort criteria used by filesort operation. ()

• EXPLAIN used to show incorrect information about how the optimizer resolved ORDER BY

Optimizations

• Connection setup was made faster by moving creation of THD to new thread ()

• Pushdown conditions into non-mergeable views/derived tables (, ) — Original code from Galina Shalygina

• has been re-implemented so as not to lock the entire table when collecting engine independent statistics ()

• Internal CRC32 routines use the optimized implementation on Power8 —

Compatibility

• 88 new added. In NO PAD collations, end spaces are significant in comparisons () — Original code from Daniil Medvedev

• MariaDB now works when started with a MySQL 5.7.6+ data directory ()

CONNECT

• for the CONNECT storage engine ()

• The CONNECT engine now supports the ()

System Variables

For a list of all new system variables, see . Variable changes include:

• New variable to disable deadlock detection

• has been renamed to ()

• Default values of the and system variables changed to BACKUP,QUICK

• The server version can now be faked to work around dated applications that require a particular

Status Variables

For a list of all new status variables, see .

Scripts

• Continuous binary log backup has been added to ()

• and mysqlbug have been removed (, )

Other Changes

• Added support for OpenSSL 1.1 and LibreSSL ()

• Persistent for InnoDB ()

• Support COM_RESET_CONNECTION ()

• "fast mutexes" have been removed. These aren't faster than normal mutexes, and have been disabled by default for years ()

Security Vulnerabilities Fixed in

For a complete list of security vulnerabilities (CVEs) fixed across all versions of MariaDB, see the page.

• :

• :

• :

• :

Comparison with MySQL

List of All Releases

See Also

• Plans for 10.x for features under consideration for features under consideration