$ vi /etc/yum.repos.d/MariaDB.repo
[mariadb]
name = MariaDB
baseurl = http://yum.mariadb.org/5.5/centos6-amd64
gpgkey=https://yum.mariadb.org/RPM-GPG-KEY-MariaDB
gpgcheck=1

update user set password=password(‘myroot’) where user=’root’;
grant all privileges on *.* to ‘root’@’%’ identified by ‘myroot’ with grant option;