mysql 设置不了短串密码怎么办 You must reset your password using ALTER USER statement before executing this statement.
centos7+ 安装 mysq 5.7 https://www.linuxidc.com/Linux/2016-09/135288.htm
set global validate_password_policy=0;
set global validate_password_length=4;
再授权
GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY 'root' WITH GRANT OPTION;
初次安装完使用后报：MySQL Packet for query is too large
解决办法：
1.首先在控制台查询一下：SHOW VARIABLES LIKE '%max_allowed_packet%';
2.set global max_allowed_packet = 5*1024*1024*10;