IBM recently released a current version of the MariaDB database to run natively in PASE on IBM i. The software installs in minutes on IBM i via the Yum-based Open Source Package Management process which is part of Access Client Solutions (ACS). This means that MySQL is once again being fully embraced as a valid IBM i database for storing data for PHP applications such as WordPress. No need to look elsewhere to host your PHP applications and MariaDB data.
If you're interested in using MariaDB on IBM i, check out the following tutorial I created on Github that can be used to quickly install and get started with MariaDB on IBM i. Install MariaDB on IBM i