mysql - 匹配多个列值的 SQL 查询

Question

我无法解决以下问题。

给定以下表结构和数据，我如何选择匹配两个标签的记录。例如:

+-----------------+------------------+
|  collection_id  |         tag      |
+-----------------+------------------+
|        1        |    advertising   |
|        1        |     tutorials    |
|        2        |    advertising   |
|        2        |       coding     |
+-----------------+------------------+

如果我搜索广告 && 教程，它应该返回 collection_id = 1，而不是 collection_id = 2。

欢迎任何指点。

Answer 1

SELECT collection_ID
FROM tableName
WHERE tag IN ('advertising','tutorials')
GROUP BY collection_ID
HAVING COUNT(*) = 2

• SQLFiddle Demo

如果未在每个 collection_ID 的标签上指定 unique 约束

SELECT collection_ID
FROM tableName
WHERE tag IN ('advertising','tutorials')
GROUP BY collection_ID
HAVING COUNT(DISTINCT tag) = 2

• SQLFiddle Demo