登录数据后。选择 mysql 数据库
use mysql;
修改密码
update user set authentication_string=PASSWORD("mynewpassword") where user='root';
更新密码直接报错
ERROR 1819 (HY000): Your password does not satisfy the current policy requirements
设置密码安全机制
set global validate_password_policy=0;
再更新密码，然后刷新会话
flush privileges;