Question

SELECT M.post_id, M.uid_fk, M.message, M.image1,M.roles, M.created,U.uname, U.f_name, U.l_name
 FROM posts M, person U
 WHERE M.uid_fk=U.p_id
    AND M.uid_fk in (
      (select send_id from friend_request where p_id = '7' AND status=1)
        or
     (select p_id from friend_request where send_id = '7' AND status=1) 
        AND
     (select send_id from follower_request where p_id = '7' AND status=1 AND M.uid_fk = '7')
        AND 
     M.uid_fk = 7
  )
 order by M.post_id DESC

我无法获得当前数据。

如何获得这样的查询

SELECT M.post_id, M.uid_fk, M.message, M.image1,M.roles, M.created,U.uname, U.f_name, U.l_name
 FROM posts M, person U
 WHERE M.uid_fk=U.p_id
  AND M.uid_fk in (1,2,3,4,7,8,9)
 order by M.post_id DESC

Answer 1

查看您的查询，我想您想获取在friend_request或follower_request表中具有条目的帖子数据。如果这就是您的意思，则可以对查询使用UNION：

SELECT M.post_id, M.uid_fk, M.message, M.image1,M.roles, M.created,U.uname, U.f_name, 
U.l_name
FROM posts M, person U
WHERE 
   M.uid_fk = 7
   AND M.uid_fk=U.p_id
   AND M.uid_fk in (select send_id from friend_request where p_id = M.uid_fk AND 
   status=1)

UNION ALL

SELECT M.post_id, M.uid_fk, M.message, M.image1,M.roles, M.created,U.uname, U.f_name, 
U.l_name
FROM posts M, person U
WHERE 
   M.uid_fk = 7
   AND M.uid_fk=U.p_id
   AND M.uid_fk in (select p_id from friend_request where send_id = M.uid_fk AND 
   status=1) 

UNION ALL

SELECT M.post_id, M.uid_fk, M.message, M.image1,M.roles, M.created,U.uname, U.f_name, 
U.l_name
FROM posts M, person U
WHERE 
   M.uid_fk = 7
   AND M.uid_fk=U.p_id
   AND M.uid_fk in (select send_id from follower_request where p_id = M.uid_fk AND 
   status=1)
ORDER BY post_id DESC

Answer 2

很难知道您的实际意图，但这可能会有所帮助。

SELECT M.post_id, M.uid_fk, M.message, M.image1,M.roles, M.created,U.uname, U.f_name, U.l_name
FROM posts M
INNER JOIN person U ON M.uid_fk=U.p_id
WHERE  M.uid_fk = 7
AND  ( 
           M.uid_fk in (select send_id from friend_request where p_id = '7' AND status=1)
        OR M.uid_fk in (select p_id from friend_request where send_id = '7' AND status=1)
        )
AND M.uid_fk in(select send_id from follower_request where p_id = '7' AND status=1)
ORDER BY M.post_id DESC

您不能在内部包含OR in()，但可以通过OR将两个in()连接起来

如何选择更多然后3表添加选择IN功能

2 个答案: