禁止、允许MySQL root用户远程访问权限

关闭MySQL root用户远程访问权限：

use mysql;
update user set host = "localhost" where user = "root" and host = "%";
flush privileges;

打开MySQL root用户的远程访问权限：

危险操作！！！

use mysql;
update user set host = "%" where user = "root";
flush privileges;