如何编写实现Excel SUMIFS功能的SQL查询

Question

我有一个这样的表：

Date        Sales   Department Store
02/01/2012   4.09    Toys       A
03/01/2012   5.90    Toys       A
02/01/2012   6.64    Toys       B
03/01/2012   4.71    Toys       B
02/01/2012   16.72   Toys       C
03/01/2012   1.37    Toys       C
02/01/2012   13.22   Movies     A
03/01/2012   18.06   Movies     A
02/01/2012   5.97    Movies     B
03/01/2012   16.71   Movies     B
02/01/2012   15.38   Movies     C
03/01/2012   19.75   Movies     C

并想要一个这样的表，其中仅考虑商店A和B：

Date        Toys    Movies
02/01/2012   10.73   19.19 
03/01/2012   10.61   34.77

这是我们将在EXCEL中使用的SUMIFS函数：

=SUMIFS(Value;Date;$H4;Department;I$3;Store;"<>C")

我们可以用SQL编写什么？

考虑到这是一个简短的例子，数据库表有30多个部门和更多的日期。我正在使用脚本

SELECT DISTINCT Date,
ISNULL(MAX(CASE WHEN Department = 'Toys'  AND Store = 'A' THEN Sales END),0) +
ISNULL(MAX(CASE WHEN Department = 'Toys'  AND Store = 'B' THEN Sales END),0) [Toys],
ISNULL(MAX(CASE WHEN Department = 'Movies'  AND Store = 'A' THEN Sales END),0) +
ISNULL(MAX(CASE WHEN Department = 'Movies'  AND Store = 'B' THEN Sales END),0) [Movies]
FROM Table$
GROUP BY Date
ORDER BY Date

…但是效率不高。感谢您的提示。

Answer 1

您的查询还可以，但可以进行一些改进：

SELEC Date,
      MAX(CASE WHEN Department = 'Toys' THEN Sales else 0 END) as [Toys],
      MAX(CASE WHEN Department = 'Movies' THEN Sales else 0 END) as [Movies]
FROM Table$
WHERE store in ('A', 'B')
GROUP BY Date
ORDER BY Date;

这将删除distinct，而对于则不需要group by。它将条件store移到该where子句上，因为它适用于所有行。并且，它ISNULL()通过else 0在case语句中包括来删除，因此该部门中没有销售的商店将返回0而不是NULL。