Question

在过去的几天里，我一直在尝试创建一个SQL查询来显示朋友之间的帖子。但是，我无法弄清楚我做错了什么。对我而言，这些帖子看起来像是重复，并且表现得与我的内涵不同。

这个查询“应该”显示来自我和我的朋友的帖子。

SELECT *
FROM bhost_entries
WHERE
  author_u_id='$user_info[u_id]'
  OR author_u_id IN (SELECT follower_u_id
                     FROM bhost_userfollow
                     WHERE following_u_id='$user_info[u_id]')
ORDER BY e_id DESC

表：

bhost_entries:     e_id, author_u_id, title
bhost_userfollow:  uf_id, following_u_id, follower_u_id

我完全偏离了轨道吗？感谢任何想法。

输出（关注2位用户时）

Heihei
Aker Brygge-spesial
Vi har oppdatert retningslinjene
Hei, dette er en kladd!
To do list
Testinnlegg
Push Notifications
Californication
Hank Moody
Hei bloggen
Heihei
Aker Brygge-spesial
Vi har oppdatert retningslinjene
Hei, dette er en kladd!
To do list
Testinnlegg
Push Notifications
Californication
Hank Moody
Hei bloggen

Answer 1

如果我可以测试一下，我会这样做：

SELECT e_id, author_u_id, title
FROM bhost_entries, bhost_userfollow
WHERE
  author_u_id='$user_info[u_id]'
  OR (follower_u_id='$user_info[u_id]' AND following_u_id=author_u_id)
ORDER BY e_id DESC
GROUP BY e_id

Answer 2

您可以尝试这样的事情：

SELECT DISTINCT (e.e_id) AS entry_id,
       e.title AS entry_title, 
       e.author_u_id AS author_id
FROM bhost_entries AS e
JOIN bhost_userfollow AS f
ON (f.following_u_id = e.author_u_id) 
WHERE (e.author_u_id = '$user_info[u_id]' OR f.follower_u_id = '$user_info[u_id]')

如果我理解正确就可以了。在这里查看：SQL Fiddle

使用JOIN显示朋友帖子

2 个答案: