说明：命令从上往下
yum install mysql* 安装mysql相关依赖
yum install mariadb-server
systemctl start mariadb.service
mysqladmin -u root password xxxx 设置root用户密码
mysql -uroot -p xxxx 登录mysql
grant all privileges on *.* to root@'%' identified by '******' ***表示数据库连接密码，设置允许远程连接