这不起作用：
DELETE FROM topics AS t , posts AS p USING t INNER JOIN p
WHERE t.id=p.topic_id AND t.id = '5599';
而这样做：
DELETE FROM topics, posts USING topics INNER JOIN posts
WHERE topics.id=posts.topic_id AND topics.id = '5599';
在 DELETE 语句中使用表别名是无效的还是有其他方法？
我的目标是删除 ID 为 5599 的所有主题和相关帖子posts.topic_id= 5599