Mysql 删除带有两个表的SQL

此SELECT查询运行良好：

SELECT u.user_id, u.user_lastvisit, n.user_id, n.multiple_counter, n.notification_id
FROM 
users u, notifications n
WHERE 
u.user_id = n.user_id
AND 
u.user_lastvisit < ( UNIX_TIMESTAMP( ) -1814400 ) 

我必须删除通知表中的每个条目。我试过这个：

DELETE notification_id FROM notifications
(SELECT u.user_id, u.user_lastvisit, n.user_id, n.multiple_counter, n.notification_id
FROM 
users u, notifications n
WHERE 
u.user_id = n.user_id
AND 
u.user_lastvisit < ( UNIX_TIMESTAMP( ) -1814400 ) )

谢谢你的帮助

删除语句的语法错误。请改用以下解决方案：

DELETE FROM notifications 
WHERE notification_id IN (
    SELECT x.notification_id
    FROM (
        SELECT notifications.notification_id
        FROM users, notifications
        WHERE users.user_id = notifications.user_id
    ) AS x
    WHERE x.user_lastvisit < (UNIX_TIMESTAMP() - 1814400)
);

---

首先，您不能在FROM子句中指定更新的目标表“通知”是否要更新或删除？你的问题是关于删除！删除但这是错误消息-second solutions gives:检查与您的MySQL服务器版本对应的手册，以了解在n.user_id=u.user_id上使用近'internal JOIN users u ON n.user_id=u.user_id，其中u.user_lastvisit再次尝试，给出：您不能为FROM子句中的更新指定目标表'notifications'

DELETE FROM notifications
    INNER JOIN users ON notifications.user_id = users.user_id 
WHERE users.user_lastvisit < (UNIX_TIMESTAMP() - 1814400)