Question

我可以请求您提供以下帮助吗？

我正在尝试计算结果中从一条记录到下一条记录的更改。如果我向您展示我当前的查询和结果，它可能会有所帮助......

SELECT A.AuditDate, COUNT(A.NickName) as [TAccounts],
       SUM(IIF((A.CurrGBP > 100 OR A.CurrUSD > 100), 1, 0)) as [Funded]
FROM Audits A
GROUP BY A.AuditDate;

查询给了我这些结果......

AuditDate D/M/Y         TAccounts     Funded                    
--------------------------------------------
30/12/2011              506           285
04/01/2012              514           287
05/01/2012              514           288
06/01/2012              516           288
09/01/2012              520           289
10/01/2012              522           289
11/01/2012              523           290
12/01/2012              524           290
13/01/2012              526           291
17/01/2012              531           292
18/01/2012              532           292
19/01/2012              533           293
20/01/2012              537           295

理想情况下，我想得到的结果与以下类似......

AuditDate D/M/Y         TAccounts     TChange   Funded           FChange
------------------------------------------------------------------------
30/12/2011              506           0         285              0
04/01/2012              514           8         287              2
05/01/2012              514           0         288              1
06/01/2012              516           2         288              0
09/01/2012              520           4         289              1
10/01/2012              522           2         289              0
11/01/2012              523           1         290              1
12/01/2012              524           1         290              0
13/01/2012              526           2         291              1
17/01/2012              531           5         292              1
18/01/2012              532           1         292              0
19/01/2012              533           1         293              1
20/01/2012              537           4         295              2

查看'17 / 01/2012'的行，'TChange'的值为5，因为'TAccounts'从之前的526增加到531.而'FChange'将基于'Funded'领域。我想要注意的事实是这个例子的前一行是'13 / 01/2012'。我的意思是，有些日子我没有数据（例如在周末）。

我想我需要使用SubQuery，但我真的很想弄清楚从哪里开始。你能告诉我如何得到我需要的结果吗？

我正在使用MS Access 2010

非常感谢你的时间。

约翰尼。

Answer 1

这是你可以尝试的一种方法......

SELECT B.AuditDate,B.TAccounts,
    B.TAccount - 
    (SELECT Count(NickName) FROM Audits WHERE AuditDate=B.PrevAuditDate) as TChange,
    B.Funded - 
    (SELECT Count(*) FROM Audits WHERE AuditDate=B.PrevAuditDate AND (CurrGBP > 100 OR CurrUSD > 100)) as FChange
FROM (
SELECT A.AuditDate,
    (SELECT Count(NickName) FROM Audits WHERE AuditDate=A.AuditDate) as TAccounts,
    (SELECT Count(*) FROM Audits WHERE (CurrGBP > 100 OR CurrUSD > 100)) as Funded,
    (SELECT Max(AuditDate) FROM Audits WHERE AuditDate<A.AuditDate) as PrevAuditDate
FROM
(SELECT DISTINCT AuditDate FROM Audits) AS A) AS B

我没有使用Group By而是使用subquerys同时获得TAccounts和Funded，以及之前的审核日期，然后在主SELECT语句中使用它来获得TAccounts和Funded再次，但这次是前一个日期，以便可以对他们进行任何所需的计算。

但我想这可能会很慢处理

Answer 2

很遗憾MS在Access中从未使这类事情变得简单，你在报告中使用了多少行？

如果它低于65K，那么我建议将数据转储到Excel电子表格中，并使用简单的公式来计算行之间的差异。

Answer 3

您可以尝试以下内容（sql未经测试，需要进行一些更改）

选择

    A.AuditDate,
    A.TAccounts,
    A.TAccounts - B.TAccounts AS TChange,
    A.Funded,
    A.Funded - B.Funded AS FChange

这

(  SELECT 
        ROW_NUMBER() OVER (ORDER BY AuditDate DESC) AS ROW, 
        AuditDate, 
        COUNT(NickName) as [TAccounts],
        SUM(IIF((CurrGBP > 100 OR CurrUSD > 100), 1, 0)) as [Funded]
    FROM Audits
    GROUP BY AuditDate
) A

INNER JOIN

(   SELECT 
        ROW_NUMBER() OVER (ORDER BY AuditDate DESC) AS ROW, 
        AuditDate, 
        COUNT(NickName) as [TAccounts],
        SUM(IIF((CurrGBP > 100 OR CurrUSD > 100), 1, 0)) as [Funded]
    FROM Audits
    GROUP BY AuditDate
) B ON B.ROW = A.ROW + 1

计算与先前记录的差异

3 个答案: