[英]MySQL query, can't figure out how to fetch the correct data
此查询与我尝试过的最复杂的查询相邻。
我的表格:(我删除了不相关的数据)
mysql> describe Posts;
+-----------+---------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-----------+---------+------+-----+---------+----------------+
| id | int(11) | NO | PRI | NULL | auto_increment |
| Time | int(11) | YES | MUL | NULL | |
+-----------+---------+------+-----+---------+----------------+
mysql> describe Containers;
+----------+-------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+----------+-------------+------+-----+---------+----------------+
| id | int(11) | NO | PRI | NULL | auto_increment |
| pid | int(11) | YES | MUL | NULL | |
| iid | int(11) | YES | | NULL | |
+----------+-------------+------+-----+---------+----------------+
mysql> describe Images;
+--------------+--------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+--------------+--------------+------+-----+---------+----------------+
| id | int(11) | NO | PRI | NULL | auto_increment |
| LocalPath | varchar(100) | YES | | NULL | |
| Category | varchar(20) | YES | | NULL | |
+--------------+--------------+------+-----+---------+----------------+
关系:
Posts.id> Containers.pid
Containers.iid> Images.id
我想要:
获取所有Posts,其中相应的Images.Category是value1,value2或value3之一。 按Posts.Time订购帖子。
伪代码:在WHERE Images.Category IN('value1','value2,'value3')ORDER BY Posts.Time DESC中获取所有数据。
尝试:
SELECT * FROM Images I
INNER JOIN Containers C ON C.iid = I.id
INNER JOIN Posts P ON C.pid = P.id
WHERE I.Category IN('value1','value2','value3');
结果:好的,但是没有按Posts.Time对Posts进行排序。
SELECT * FROM Posts P
INNER JOIN Containers C ON P.id = C.pid
RIGHT OUTER JOIN Images I ON C.iid = I.id
WHERE I.Category IN('value1','value2','value3')
ORDER BY P.Time DESC;
结果:获取不包含Images.Category的帖子行。
希望我的提问格式正确,感谢您的宝贵时间。
尝试这个:
SELECT * FROM Images I
INNER JOIN Containers C ON C.iid = I.id
INNER JOIN Posts P ON C.pid = P.id
WHERE I.Category IN('value1','value2','value3')
ORDER BY P.Time DESC;
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