根据类似于mysql的标签选择相关标题
问题描述：
标签
tag_id post_id value
------------------------
1 1 some
2 1 good
3 1 title
4 2 some
5 2 good
6 3 some
7 4 good
8 4 title
帖子
post_id title
-------------------
1 some good title
2 some good
3 some
4 good title
我们如何获得在同一post_id中包含值 some和good 的post_id = 1和2?
how can we get the post_id = 1 and 2 that contains value some and good in the same post_id?
所以结果是
RESULT
title
----------
some good title
some good
good title剂量显示，因为标签的post_id = 4中没有some值.
some不显示要求good
good title dosent show becouse there is no some value in post_id = 4 in tags.
some doesnt show beouse the requirement good
答
多次尝试
Try LIKE multiple time:
SELECT * FROM post
WHERE title LIKE '%some%'
AND title LIKE '%good%'
请参阅此SQLFiddle
您还可以像这样连接两个表:
See this SQLFiddle
You can also join both tables like this:
SELECT post.post_id, title FROM Post
RIGHT JOIN Tags
ON post.post_id = tags.post_id
WHERE Tags.value IN ('some','good')
GROUP BY post.Post_ID
HAVING COUNT(*)>1;
请参阅此SQLFiddle
注意:如果不使用HAVING子句，它还将返回存在任何单个值的记录
See this SQLFiddle
Note: If we don't use HAVING clause, It will also return records where any single value exists