MariaDB is one of the most popular database servers. Made by the original developers of MySQL.
You can create and manage databases directly from inside the MariaDB container but we recommend you use phpMyAdmin to manage your databases.
We heavily recommend that if you spin up a container that requires a database you create a user for that container in phpMyAdmin. You should NEVER use the root account for anything other than database management.
Note: The root password cannot be longer than 32 characters (Source). We also noticed that phpMyAdmin will not work with complex passwords longer than 16 characters. It seems to only support uppercase, lowercase and numbers.