CentOS 7的yum源中貌似没有正常安装mysql时的mysql-sever文件，需要去官网上下载
# wget http://dev.mysql.com/get/mysql-community-release-el7-5.noarch.rpm # rpm -ivh mysql-community-release-el7-5.noarch.rpm # yum install mysql-community-server
成功安装之后重启mysql服务
# service mysqld restart
初次安装mysql是root账户是没有密码的
设置密码的方法
# mysql -uroot mysql> set password for ‘root’@‘localhost’ = password(‘mypasswd‘); mysql> exit
搞定！