Which databases are supported by xoops?

At the time of writing, XOOPS only supports a MySQL database. Support for other databases is in the planning phase, but so far the need for this functionality has been limited and the XOOPS team believes that it is better to support one database 100% than supporting many more databases 70%.

This Q&A was found on XOOPS Web Application System : https://xoops.org/modules/smartfaq/faq.php?faqid=98