一、安装mysql官方yum源
在MySQL官网中下载YUM源rpm安装包：http://dev.mysql.com/downloads/repo/yum/
下载yum源
wget http://dev.mysql.com/get/mysql57-community-release-el7-8.noarch.rpm
安装yum源
yum localinstall mysql57-community-release-el7-8.noarch.rpm
查看mysql相关yum包的名字，如果正常显示下图则证明安装成功
yum repolist enabled | grep "mysql.*-community.*"
如果想修改mysql的默认yum安装版本可以在yum源文件/etc/yum.repos.d/mysql-community.repo修改enabled值为1为生效，为0则不生效
二、安装mysql
yum install mysql-community-server
三、启动mysql
systemctl start mysqld
4、查看mysql状态
systemctl status mysqld
5、设置开机启动
systemctl enable mysqld
systemctl daemon-reload
6、查看root默认密码并修改
查看默认默认密码
grep 'temporary password' /var/log/mysqld.log
修改密码
mysql -uroot -p
ALTER USER 'root'@'localhost' IDENTIFIED BY 'MySqlPasswd1!';
或者
set password for 'root'@'localhost'=password('MyNewPass4!');
如果要修改成root123这样小于八位的简单密码则需要修改密码策略。将策略要求置为LOW，长度要求置为6
set global validate_password_policy=0;
set global validate_password_length=6;
然后修改密码
alter user 'root'@'localhost' identified by 'root123';