How to install MariaDB
sudo apt-get update
sudo apt-get install mariadb-client-10.1 mariadb-common mariadb-server-10.1 mariadb-server-core-10.1 mariadb-client-core-10.1
To remove mariadb and all files
sudo apt-get remove --purge mariadb-client-10.1 mariadb-common mariadb-server-10.1 mariadb-server-core-10.1 mariadb-client-core-10.1
sudo atp-get autoremove -y
sudo apt-get autoclean
sudo rm -rf /etc/mysql