Download MariaDB 10.4.2

MariaDB originated as a fork of MySQL, after it was acquired by Oracle in 2009-2010. For an overview of the differences between MariaDB and MySQL you can visit: this one and this one pages right. MariaDB is a powerful open source database server, which is especially popular as a website and forum database. The developers have released version 10.4.2, noting that this is currently a development branch of MariaDB. The abbreviated announcement of this release is as follows:

MariaDB 10.4.2 Release Notes

MariaDB 10.4 is the current development series of MariaDB. It is an evolution of MariaDB 10.3 with several entirely new features not found anywhere else and with backported and reimplemented features from MySQL. MariaDB 10.4.2 is a Beta release.

Thanks, and enjoy MariaDB!

Notable changes of this release include:

• Galera 4 version 26.4.0 has been added in this release, see the Galera 4 Notes section for details
• a number of bugs related to MDEV-15562 Instant DROP COLUMN have been fixed
• New variable, max_password_errors for limiting the number of failed connection attempts by a user.

Gallery 4 Notes

Upgrading to Galera 4 version 26.4.0
Rolling upgrades from earlier 10.3 (or older) MariaDB releases are not supported in this release. For upgrading a 10.3-based cluster, any applications accessing the cluster should be stopped and the cluster shut down. Then for each cluster node the following procedure should be carried out:

• Install MariaDB 10.4.2 and Galera 4 version 26.4.0
• Start MariaDB server, but make sure it is not trying to connect to the cluster by configuring wsrep_provider=none
• While MariaDB server is running, run mysql_upgrade for the server
• Stop MariaDB server

After that, you can bootstrap the cluster. If there was ongoing application load on the cluster during the initial cluster shutdown phase, you should make sure to bootstrap the cluster with the node which was shutdown last.

We are working on rolling upgrade support for the final GA version of MariaDB 10.4. With a rolling upgrade, a live cluster can be upgraded node by node, and the cluster is able to process application load when having a hybrid setup of 10.3 and 10.4 nodes.

New Features in Galera 26.4.0
The ‘mysql’ schema contains new Galera replication related tables:

• wsrep_cluster
• wsrep_cluster_members
• wsrep_streaming_log

End users may read but not modify these tables.

The new streaming replication feature allows replicating transactions of unlimited size. With streaming replication, a cluster is replicating a transaction in small fragments during transaction execution. This transaction fragmenting is controlled by two new configuration variables:

• wsrep_trx_fragment_unit (bytes, rows, statements) defines the metrics for how to measure transaction size limit for fragmenting. Possible values ​​are:
  • bytes: transaction’s binlog events buffer size in bytes
  • rows: number of rows affected by the transaction
  • statements: number of SQL statements executed in the multi-statement transaction
• wsrep_trx_fragment_size defines the limit for fragmenting. When a transaction’s size, in terms of the configured fragment unit, has grown over this limit, a new fragment will be replicated.

Transactions replicated through galera replication will now process the commit phase using MariaDB’s group commit logic. This will affect transaction throughput, especially when binary logging is enabled in the cluster.

Limitations in Galera 26.4.0
Upgrading from 10.3 version 25.3.25 to 10.4.2 version 26.4.0 must happen on a stopped cluster. Only after all nodes have been upgraded to MariaDB 10.4.2 and Galera 26.4.0 can the cluster be started up Splitting transactions of LOAD DATA execution will conflict with streaming replication, and should not be used if streaming replication is configured