Release Notes for MariaDB Enterprise Server 10.3.18-3

This third release of MariaDB Enterprise Server 10.3 is a maintenance release, including a variety of fixes.

MariaDB Enterprise Server 10.3.18-3 was released on 2019-09-30.

Issues Fixed

Can result in data loss

• Due to a race condition in InnoDB, an exclusive lock to an inserted record could be wrongly granted to multiple transactions when the INSERT transaction commits. This could lead to a server crash or data loss. (MDEV-15326)

• INSERT...ON DUPLICATE KEY UPDATE, when there is more than one key, could result in inconsistent data between master and slave for replication mode MIXED and STATEMENT. This has been fixed for MIXED, but cannot be controlled by the replication for STATEMENT based replication.

• Inconsistent Slaves need to be set up again from the Master. (MDEV-17614)

• Wrong value on instantly added column can occur after DELETE and a following UPDATE of PRIMARY KEY. (MDEV-20066)

Can result in a hang or crash

• Replication could hang for InnoDB transactions as InnoDB has its own concurrency control innodb_thread_concurrency. (MDEV-20247)

• Fix potential crash in ON UPDATE CASCADE when the foreign table is system versioned. (MDEV-20311)

Can result in unexpected behavior

• After setting SET foreign_key_checks=0 it is possible to drop indexes from referenced (parent) tables, which could cause InnoDB to behave as if table doesn't exist in engine (MDEV-17187)

• Fix for corner case where MariaDB Backup could fail because encrypted data files could not be copied if created shortly before the backup was started. (MDEV-18128)

• MariaDB Backup could fail in the prepare face if the redo log is bigger than 512GB. (MDEV-20060)

• Basic 3-way join queries are not parsed. (MDEV-19421)

Related to performance

• Optimized scanning of the undo log versions while scanning the secondary index versions. (MDEV-20301)

Interface Changes

• in_predicate_conversion_threshold system variable added

• mysqld --in-predicate-conversion-threshold command-line option added

Platforms In alignment to the enterprise lifecycle, MariaDB Enterprise Server 10.3.18-3 is provided for:

• CentOS 8

• CentOS 7

• CentOS 6

• Debian 10

• Debian 9

• Debian 8

• Red Hat Enterprise Linux 8

• Red Hat Enterprise Linux 7

• Red Hat Enterprise Linux 6

• Ubuntu 18.04

• Ubuntu 16.04

• Microsoft Windows

Some components of MariaDB Enterprise Server might not support all platforms. For additional information, see "MariaDB Corporation Engineering Policies".