Question

我正在尝试创建一个基于以下内容返回结果的查询：

该脚本现在适用于我，但我需要执行额外的步骤。我需要弄清楚如何筛选出任何＆＃39; activity.dest_id＆＃39;的结果。尚未在＆＃39; user_requests＆＃39;中确认表格并仅将其应用于＆＃39; IN＆＃39;中的最后一个值。在示例中，值将是＆＃39;比尔＆＃39;所有其他价值观，如时尚，艺术，建筑和＃39;不必对user_requests表进行检查，因为这些值不是人。谢谢你的帮助。

SELECT a.activity_type, a.dest_id, o.opinion_id, o.fromUser, o.image_data, o.votedYes, o.votedNo, o.created_at, o.expires_at
FROM activity a, opinions o
WHERE a.opinion_id = o.opinion_id
AND NOT
EXISTS (
SELECT opinion_id, fromUser
FROM user_activity u
WHERE u.opinion_id = a.opinion_id
)
AND a.dest_id
IN (
"Fashion", "Art", "Architecture", "Bill"
)

 user_activity table
+------------+-----------+
| opinion_id | fromuser 
------------+-----------+ 
| 9          | Jim   
| 10         | Sam  
+------------+-----------+

 user_requests table
+------------+-----------+---------+
| fromUser | toUser | type | status
------------+-----------+----------+ 
| Ana      | Bill   | C    |   1
| Kate     | Bill   | P    |   0
+------------+-----------+---------+

 activity table
+------------+-------+
| fromUser | dest_id
------------+--------+ 
| Ana      | Fashion   
| Ana      | Art   
| Kate     | Bill   
| Tom      | Fashion   
| Bill     | Fashion   
| Kim      | Art   
| Kim      | Art  
| Ana      | Fashion
| Kim      | Ana
+------------+-------+

 opinion table
+------------+-----------+---------+------------+-----------+---------+--------------+
| opinion_id | fromUser | image_data | votedYes | votedNo | created_at | expires_at
+------------+-----------+---------+------------+-----------+---------+--------------+
| 1          | Ana      | non        |   1      |  3      | 2014-12-17 | 2014-12-18 
| 2          | Ana      | non        |   1      |  3      | 2014-12-17 | 2014-12-18 
| 3          | Ana      | non        |   1      |  3      | 2014-12-17 | 2014-12-18 
| 4          | Ana      | non        |   1      |  3      | 2014-12-17 | 2014-12-18 
| 5          | Ana      | non        |   1      |  3      | 2014-12-17 | 2014-12-18 
+------------+-----------+---------+------------+-----------+---------+-------------+

Answer 1

看起来你需要加入。我正确地假设您需要将user_activity表中的fromuser与user_requests表中的fromuser一起加入。

P =待定和C =确认

如果这是正确的，

SELECT * FROM (
SELECT a.activity_type, a.dest_id, o.opinion_id, o.fromUser, o.image_data, o.votedYes, o.votedNo, o.created_at, o.expires_at
FROM activity a, opinions o
WHERE a.opinion_id = o.opinion_id
AND NOT
EXISTS (
SELECT opinion_id, fromUser
FROM user_activity u
WHERE u.opinion_id = a.opinion_id
)
AND a.dest_id
IN (
"Fashion", "Art", "Architecture", "Bill"
)
) x INNER JOIN user_requests ON x.fromUser = user_requests.fromUser
WHERE user_requests.type = 'C'

这可能不是最有效的方法，它也是未经测试的，但它对您的查询来说似乎是最符合逻辑的。

MYSQL子查询，带有来自多表查询的过滤结果

1 个答案: