用于匹配多个列值的SQL查询

Question

我无法理解以下问题。

鉴于以下表结构和数据，我如何选择与两个标记匹配的记录。例如：

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

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

欢迎提出任何指示。

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unique

的代码上指定collection_ID约束

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

• SQLFiddle Demo