根据类似于 mysql 的标签选择相关标题

Question

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

我们怎样才能得到 post_id = 1 和 2 的值 some 和 good 在同一个 post_id 中？

所以结果是

RESULT
title
----------
some good title
some good

good title dosent 显示，因为标签中的 post_id = 4 中没有 some 值。 some 不显示要求 good

Answer 1

多次尝试LIKE：

SELECT * FROM post
WHERE title LIKE '%some%'
AND title LIKE '%good%'

See this SQLFiddle

您也可以像这样连接两个表：

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;

See this SQLFiddle

注意：如果我们不使用HAVING子句，它也会返回任何单个值存在的记录

See this SQLFiddle

See the similar requirement with similar table structure.