Centos安装MySql5.5(yum安装)

rpm -qa | grep mysql
rpm -qa | grep mariadb
rpm -e --nodeps #上边命令查询的结果

rpm -ivh http://repo.mysql.com/yum/mysql-5.5-community/el/6/x86_64/mysql-community-release-el6-5.noarch.rpm
修改/etc/yum.repos.d/mysql-community.repo文件，将5.5的enabled改为1，5.6的enabled改为0
不改安装的是5.6版本

yum install -y mysql-community-client mysql-community-devel mysql-community-server
因为是国外的链接，可能有些慢，建议白天安装
初始化
service mysqld start

chkconfig mysqld on

/usr/bin/mysqladmin -u root password '新密码'

登录
mysql -u root -p
允许远程访问
grant all privileges on *.* to root@"%" identified by "新密码" with grant option;
FLUSH PRIVILEGES;

启动：service mysqld start
停止：service mysqld stop
重启：service mysqld restart
状态：service mysqld status