This is the second part of the process of creating the mail server on a CentOS 8. If you came here by accident, You should read first the previous publication on the Instalação dos Pacotes

Why use MariaDB/MySQL?

First of all I must clarify that I prefer to use PostgreSQL instead of MariaDB/MySQL for many reasons, However, There is one that weighs against the use of PostgreSQL in a unified server with WordPress and E-mail services is the simple fact that WP does not have native support for PostgreSQL. You can have more information on this topic on the official WordPress documentation This link. How am I basing on personal experience to write this document and also for small services, I'm using the most common and most accessible. If the use of PostgreSQL is of your interest, You can consult this document later where I'll show you how to migrate from MariaDB for PostgreSQL.

Configuring MariaDB/MySQL

Assuming that you are following the steps of this manual, You'll be with an installation of MariaDB still not configured. If you already have a functional installation, You can skip to the next step.