While MySQL can be used as a database for The Arsse, this is **not recommended** due to MySQL's technical limitations. It is fully functional, but may fail with some newsfeeds where other database systems do not. Additionally, it is particularly important before upgrading from one version of The Arsse to the next to back up your database: a failure in a database upgrade can corrupt your database much more easily than when using other database systems.
Please note that as of this writing MariaDB cannot be used in place of MySQL as it lacks features of MySQL 8 which The Arsse requires. The awkwardly-named [_Percona Server for MySQL_](https://www.percona.com/software/mysql-database/percona-server), on the other hand, should work, though this has not been tested.
You are therefore strongly advised not to use MySQL. Though our MySQL test suite ensures functionally identical behaviour to SQLite and PostgreSQL for the supplied test data in a default MySQL configuration, there are [many other subtle ways in which it can fail](https://grimoire.ca/mysql/choose-something-else), and we do not have the manpower to account for most of these with certainty.
Also please note that as of this writing MariaDB cannot be used in place of MySQL as it lacks features of MySQL 8 which The Arsse requires. The awkwardly-named [_Percona Server for MySQL_](https://www.percona.com/software/mysql-database/percona-server), on the other hand, should work, though this has not been tested.
