create user 'username'@'localhost' identified by 'password';--创建用户set password for 'username'@'localhost'=password('newpassword');--修改用户密码grant all on *.* to 'username'@'localhost';--授权revoke all on *.* to 'username'@'localhost';--撤销授权drop user 'username'@'localhost';--删除用户