Release Notes for MariaDB Enterprise Server 10.2.27-3

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 Primary and replica for replication mode MIXED and STATEMENT. This has been fixed for MIXED, but cannot be controlled by the replication for STATEMENT based replication.

Inconsistent replicas need to be set up again from the Primary. (MDEV-17614)

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

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)

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)

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