1.安装前准备
1.1安装前，我们可以检测系统是否自带安装 MySQL:
rpm -qa | grep mysql
1.2.如果你系统有安装，那可以选择进行卸载:
sudo systemctl stop mysql
sudo yum remove mysql-server mysql-client mysql-common
sudo rm -rf /etc/mysql /var/lib/mysql
2.官网选择合适的镜像
https://dev.mysql.com/downloads/repo/yum/
3.安装mysql
wget https://dev.mysql.com/get/mysql57-community-release-el7-9.noarch.rpm
rpm -ivh mysql57-community-release-el7-9.noarch.rpm
yum update
yum install mysql-server
4.权限设置，启动服务和查看运行状态
chown mysql:mysql -R /var/lib/mysql
systemctl start mysqld
systemctl status mysqld
5.msyql安装后需要做的
5.1默认的root用户密码为空，你可以使用以下命令来创建root用户的密码
mysqladmin -u root password "123456"
5.2登录服务
mysql -u root -p