wget -i -c http://dev.mysql.com/get/mysql57-community-release-el7-10.noarch.rpm
    yum -y install mysql57-community-release-el7-10.noarch.rpm
    rpm —import https://repo.mysql.com/RPM-GPG-KEY-mysql-2022
    yum -y install mysql-community-server
    systemctl start mysqld.service
    grep “password” /var/log/mysqld.log（查询mysql的初始密码）
    set password=password（‘123456’）；（登录数据库修改密码）
    关闭mysql密码强制复杂度要求：
    vim /etc/my.cnf（在文件末尾加上如下两行）
    plugin-load=validate_password.so
    validate-password=OFF