Question

这有效：

SELECT Date, Prop_Code, MBA_Account, SUM([12.31.2017_YTD]) AS Q1
FROM [2017DB]
WHERE (Date = '2017-06-30')
GROUP BY Date, Prop_Code, MBA_Account

我试图输出select语句和相同select语句之间的差异，只有第二个select语句的日期为03-31。

我相信这可以通过子查询来实现，但我是初学者并且在构建它时遇到一些困难。

这不起作用：

Select(
    SELECT Date, Prop_Code, MBA_Account, SUM([12.31.2017_YTD]) AS Q1
    FROM [2017DB]
    WHERE (Date = '2017-06-30'))
- 
    SELECT Date, Prop_Code, MBA_Account, SUM([12.31.2017_YTD]) AS Q1
    FROM [2017DB]
    WHERE (Date = '2017-03-31'))

    GROUP BY Date, Prop_Code, MBA_Account


Data >  Date    Prop_Code   MBA_Account 12.31.2017_YTD
        3/31/2017   Balt    Administrative  100
        3/31/2017   Balt    Administrative  100
        6/30/2017   Balt    Administrative  500
        6/30/2017   Balt    Administrative  500


Desired result >        Prop_Code   MBA_Account Q2
            Balt    Administrative  800

期望的结果是计算： sum（6/30 YTD记录） - 总和（3/31 YTD记录）

最终有效的代码是戈登建议的一个版本：

SELECT Prop_Code, MBA_Account,
SUM(CASE WHEN DATE = '2017-09-30' THEN [12.31.2017_YTD] END) -
SUM(CASE WHEN DATE = '2017-06-30' THEN [12.31.2017_YTD] END) AS 'Q3'
FROM [2017DB].[dbo].[2017DB]
Group by Prop_Code, MBA_Account

Answer 1

您可以使用条件聚合：

SELECT Date, Prop_Code, MBA_Account,
       SUM(CASE WHEN DATE = '2017-03-31' THEN [12.31.2017_YTD] END) AS Q1_1,
       SUM(CASE WHEN DATE = '2017-06-30' THEN [12.31.2017_YTD] END)) AS Q1_2
FROM [2017DB]
WHERE Date IN ('2017-06-30', '2017-03-31')
GROUP BY Date, Prop_Code, MBA_Account;

差异只是SUM()表达式的差异。

子查询减法 - SQL

1 个答案: