yum install mariadb-server mariadb
http://dev.mysql.com/get/Downloads/MySQL-5.7/mysql-community-server-5.7.14-1.el7.x86_64.rpm
use mysql;
update user set password=password('123456') where user='root';
grant all privileges on *.* to root@'%' identified by '123456';
flush privileges;
rpm -Uvh https://mirror.webtatic.com/yum/el7/webtatic-release.rpm