结合重复的结果

Question

我希望运行一个查询，该查询将返回客户请求表中的服务成本。请求表中有来自同一客户的多个请求。

我有查询：

SELECT REQUESTS.CUST, PRICE.COST
FROM REQUESTS
JOIN PRICE ON REQUESTS.SERV = PRICE.SERV
ORDER BY REQUESTS.CUST ASC

这将返回服务成本，如下所示：

CUST|Cost
1001|10
1002|5
1002|4

我需要这个回来

Cust|Cost
1001|10
1002|9

Answer 1

使用此

SELECT REQUESTS.CUST, SUM(PRICE.COST)
FROM REQUESTS
JOIN PRICE ON REQUESTS.SERV = PRICE.SERV
GROUP BY REQUESTS.CUST
ORDER BY REQUESTS.CUST ASC

Answer 2

您需要对客户进行分组：

SELECT REQUESTS.CUST, sum(PRICE.COST)
FROM REQUESTS
JOIN PRICE ON REQUESTS.SERV = PRICE.SERV
GROUP BY REQUESTS.CUST
ORDER BY REQUESTS.CUST ASC