SQL Sum of last X Sum of records

Question

我已经找了一段时间，但找不到这个问题的答案(也许我没有搜索正确的术语或其他东西)。基本上，我有一个数据库，每个日期有任意数量的条目。我需要取包含条目的最后 X 天的总和(忽略没有条目的天数)。我知道如何找到每天的总和。

假设我有一个名为“Yield”的表:

UnitID  Date        TestTime    NumMeasured NumPassing
1       2013-04-05  10:15       25          3
2       2013-03-31  10:12       30          1
3       2013-03-30  10:12       26          2
4       2013-03-29  10:30       11          1
5       2013-03-31  10:20       6           2
6       2013-04-05  10:30       5           0

然后我使用这个查询:

SELECT DISTINCT 
    Date, 
    (
        SELECT SUM([NumMeasured]) 
        FROM [dbo].[Yield] T1 
        WHERE T1.Date = T2.Date
    ) AS 'NumMeasured', 
    (
        SELECT SUM([NumPassing]) 
        FROM [dbo].[Yield] T1 
        WHERE T1.Date = T2.Date
    ) AS 'NumPassing' 
FROM [dbo].[Yield] T2 

要获得每天的总通过/测量:

Date        NumMeasured NumPassing
2013-03-29      11          1
2013-03-30      26          2
2013-03-31      36          3
2013-04-05      30          3

然后，我需要一个查询，我可以在某个日期调用它(比如我在 4/05 调用它)，它获取包含条目的最后 X(比如 100)天，并返回 NumMeasured 和 NumPassing 列的总和。天。我无法让这部分工作，我不断遇到我没有足够经验来解决的 SQL 问题。我正在寻找类似的东西

SELECT
    (
        SELECT TOP 100 SUM(T3.[NumMeasured]) 
        FROM T3 
        WHERE T3.Date <= '4/05/2013' 
        ORDER BY T3.Date
    ) AS 'NumMeasured', 
    (
        SELECT TOP 100 SUM(T3.[NumPassing]) 
        FROM T3 
        WHERE T3.Date <= '4/05/2013' 
        ORDER BY T3.Date
    ) AS 'NumPassing', 
    (
        SELECT DISTINCT 
            Date, 
            (
                SELECT SUM([NumMeasured]) 
                FROM [PhaseNoiseMonitoring].[dbo].[Yield] T1 
                WHERE T1.Date = T2.Date
            ) AS 'NumMeasured', 
            (
                SELECT SUM([NumPassing]) 
                FROM [PhaseNoiseMonitoring].[dbo].[Yield] T1 
                WHERE T1.Date = T2.Date
            ) AS 'NumPassing' 
        FROM [PhaseNoiseMonitoring].[dbo].[Yield] T2 
    )
AS T3

预期的查询将返回:

NumMeasured NumPassing
103         9

我意识到这是完全错误的，但我真的不知道如何使它工作。

Answer 1

这是使用相关子查询的想法:

with bydays as (<your query here>)
select bd.*,
       (select sum(NumMeasured) from (select top 100 * from bydays bd2 where bd2.date <= bd.date order by date desc) t
       ) as Measured100,
       (select sum(NumPassingd) from (select top 100 * from bydays bd2 where bd2.date <= bd.date order by date desc) t
       ) as Measured100
from bydays