如果采用命令
yum install mysql-server mysql-libs mysql
来安装mysql，报如下错误
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* base: mirrors.skyshe.cn
* extras: mirrors.zju.edu.cn
* updates: centos.ustc.edu.cn
No package mysql-server available.
Package 1:mariadb-libs-5.5.47-1.el7_2.x86_64 already installed and latest version
Package 1:mariadb-5.5.47-1.el7_2.x86_64 already installed and latest version
Nothing to do
其中，出现
No package mysql-server available.
之类的错误的话，是因为CentOs7采用MariaDB来代替Mysql，可以使用
yum -y install mariadb-server mariadb
来安装。如果要按照原来方法安装MySQL的话，添加如下语句
sudo rpm -Uvh http://dev.mysql.com/get/mysql-community-release-el7-5.noarch.rpm
这样就可以按照原来方法安装MySQL了。
