sql语句问题,一个帖子,下面很多评论。用join关联查询,下面的评论只有一条,其他的都没查出来,该怎么写呢?
回复讨论(解决方案)
贴出你的表结构和SQL看看。
贴出你的表结构和SQL看看。
id, rid被回复的帖子的id,content回复内容,uid,回复人id
select * from 评论表 where rid = 你查看的帖子id;//不明白哪里需要用到join?
不需要join啊。
select * from table where rid=帖子id;
按照ID来掉数据就可以了不涉及到其他的除非你需要将用户信息也调用出来,那有可能,否则只是读取帖子回复的话没有必要做join的。

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