MYSQL创建用户Unknown column 'plugin' in 'mysql.user'的解决方法

 执行下列sql 
ALTER TABLE `user` ADD `Create_tablespace_priv` ENUM('N','Y') NOT NULL DEFAULT 'N' AFTER `Trigger_priv`; 
ALTER TABLE `user` ADD `plugin` CHAR(64) NULL AFTER `max_user_connections`; 
ALTER TABLE `user` ADD `authentication_string` TEXT NULL DEFAULT NULL AFTER `plugin`; 
ALTER TABLE `user` ADD `password_expired` ENUM('N','Y') NOT NULL DEFAULT 'N' AFTER `authentication_string`;