从另一个表中检索数据信息 Left Join SQL

Jean 发表于 Dev

让

用户 A 点赞了用户 C 的帖子

表用户：

id_user name
 1      A
 2      B
 3      C

桌帖：

 id_post    post            user_post
   15       hi                  2
   19       how are you         3
   23       hello               2

表喜欢：

   id_like  id_liker liked_post_id  liked_user_id
   45           1           19          3

从table likes我显示结果

用户 1 喜欢了属于用户 3 的帖子 19

SELECT liked_user_id,_liker,liked_post_id 
FROM likes
WHERE liked_user_id = 3

如何显示下一个

用户 A 喜欢用户 C 的帖子“你好吗”

我试过了，但出现错误：

 SELECT name
 FROM users as u
 LEFT JOIN 
     (SELECT id_post, post, user_post
      FROM posts as p
      LEFT JOIN 
          (SELECT liked_user_id, id_liker, liked_post_id 
           FROM likes 
           WHERE liked_user_id = 3
          ) AS b ON u.id_post = b.liked_post_id
     ) AS c ON u.id_user = c.user_post

重击

SELECT u.`name`, v.`name`, p.post  
FROM likes 
LEFT JOIN Users as u on likes.id_liker=u.id_user
LEFT JOIN Users as v on likes.liked_user_id=v.id_user
LEFT JOIN Posts as p on likes.liked_post_id=p.id_post
WHERE likes.liked_user_id=3

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