Question

假设我有这两个表：

|Customers     |          |Purchases      |
----------------          -----------------
|CusID         |-----     |PurchaseID     |
|CusName       |     |---<|CusID          |
|CusAge        |          |ItemName       |
|CusDateAdded  |          |DatePurchased  |

我需要通过多个ItemNames过滤我的结果集。假设我想要退回购买“相机”和“手机”的所有年龄在18到24岁之间的客户。我可以运行以下查询来获取年龄范围之间的客户的所有记录：

SELECT CusID
FROM Customers AS C
JOIN Purchases AS P
ON C.CusID = P.CusID
WHERE C.CusAge BETWEEN 18 AND 24

但是，当需要过滤购买表中的ItemName列时，如何在多行上进行过滤？假设没有多个查询可以吗？

Answer 1

SELECT C.CusID
FROM Customers AS C
JOIN Purchases AS P ON C.CusID = P.CusID
WHERE C.CusAge BETWEEN 18 AND 24
AND ItemName IN ('camera','phone')
GROUP BY C.CusID
HAVING count(distinct ItemName) = 2

由客户分组并仅返回具有这两项的人。

Answer 2

我相信这会回答您的问题： SQL FIDDLE

SELECT C.CustID,C.CustName,P.ItemName
FROM Customers AS C
JOIN Purchases AS P ON C.CustID = P.CustID
GROUP BY C.CustID,C.CustName,P.ItemName
HAVING P.ItemName IN ('camera','phone')

MySQL对多行内的列值进行过滤？

2 个答案: