The MySQL MyISAM storage engine does not support foreign key constraints or transactions. This may cause data corruption and is not recommended for use.

Since its the default storage engine for MySQL Confluence is often installed using it without any warning given to the user. Confluence will work perfectly until the lack of foreign keys and proper transaction isolation causes data corruption, at which point creating backups or upgrading can be very difficult.

It would be great to detect this storage type during Confluence boot and provide an appropriate message on the user interface and/or in the system logs.