使用MS Access数据库跟踪十二个月公式

Question

我有一个名为Cash_Flow_Statements的数据库，我需要创建一个保存的查询来计算过去十二个月（TTM）的自由现金流。

这是我的数据库的示例：

这是我保存的查询的代码。 我已经将此代码用于其他计算，所以我知道它可以工作。 我只是不知道如何在SQL中执行“十二个月”。

CREATE PROC " & Calculation & " AS _
SELECT Income_Statements.Ticker, Income_Statements.[Year], Income_Statements.Period, _
" & Formula & " AS TTM _
FROM (Income_Statements AS Income_Statements INNER JOIN Balance_Sheets AS Balance_Sheets ON (Income_Statements.Ticker = Balance_Sheets.Ticker) AND (Income_Statements.[Year] = Balance_Sheets.[Year]) AND (Income_Statements.Period = Balance_Sheets.Period)) _
INNER JOIN Cash_Flow_Statements AS Cash_Flow_Statements ON (Balance_Sheets.Ticker = Cash_Flow_Statements.Ticker) AND (Balance_Sheets.[Year] = Cash_Flow_Statements.[Year]) AND (Balance_Sheets.Period = Cash_Flow_Statements.Period)

我需要变量Formula包含方程式，该方程式将计算自由现金流的过去12个月。 这是数学的样子：

自由现金流TTM =总和（运营现金流MRQ1 +运营现金流MRQ2 +运营现金流MRQ3 +运营现金流MRQ4）-总和（资本支出MRQ1 +资本支出MRQ2 +资本支出MRQ3 +资本支出MRQ4）

MRQ =最近季度

我需要在SQL中使用此公式。 我该怎么做呢？

UPDATE

根据下面的@Gord Thompson的答案，我想出了以下代码：

SELECT Ticker, [Year], Period, (SELECT (SUM(su.Net_Cash_Flow_Operating) - SUM(su.Capital_Expenditures)) _
FROM (SELECT Ticker, [Year], Period, Net_Cash_Flow_Operating, Capital_Expenditures _
FROM Cash_Flow_Statements _
UNION ALL _
SELECT Ticker, [Year] + 1, Period - 4, Net_Cash_Flow_Operating, Capital_Expenditures _
FROM Cash_Flow_Statements) su _
WHERE su.Ticker = s.Ticker AND su.[Year] = s.[Year] AND (su.Period Between s.Period - 3 And s.Period)) _
AS SalesLast12Months _
FROM Cash_Flow_Statements AS s

当它本身运行时，它恰好返回我需要的东西。 但是，正如我在原始帖子中提到的那样，我需要能够将变量Formula设置为包含SQL语句，然后将其插入到现有的SQL语句中。

因此，我尝试适应@Gord Thompson的答案，并提出了这个建议。

式：

Formula = “(SELECT (SUM(su.Net_Cash_Flow_Operating) - SUM(su.Capital_Expenditures)) _
FROM (SELECT Ticker, [Year], Period, Net_Cash_Flow_Operating, Capital_Expenditures _
FROM Cash_Flow_Statements UNION ALL SELECT Ticker, [Year] + 1, Period - 4, Net_Cash_Flow_Operating, Capital_Expenditures _
FROM Cash_Flow_Statements) su _
WHERE su.Ticker = Cash_Flow_Statements.Ticker AND su.[Year] = Cash_Flow_Statements.[Year] AND (su.Period Between Cash_Flow_Statements.Period - 3 And Cash_Flow_Statements.Period))”

SQL语句：

"CREATE PROC " & Calculation & " AS SELECT Income_Statements.Ticker, Income_Statements.[Year], Income_Statements.Period, " & Formula & " AS TTM _
FROM (Income_Statements AS Income_Statements _
INNER JOIN Balance_Sheets AS Balance_Sheets ON (Income_Statements.Ticker = Balance_Sheets.Ticker) AND (Income_Statements.[Year] = Balance_Sheets.[Year]) AND (Income_Statements.Period = Balance_Sheets.Period)) _
INNER JOIN Cash_Flow_Statements AS Cash_Flow_Statements ON (Balance_Sheets.Ticker = Cash_Flow_Statements.Ticker) AND (Balance_Sheets.[Year] = Cash_Flow_Statements.[Year]) AND (Balance_Sheets.Period = Cash_Flow_Statements.Period)

结果如下：

再次，这是非常接近，但不是我所需要的。 我相信我知道是什么原因导致我在修改代码后无法正常工作，但还不知道如何解决。 在@Gord Thompson代码中，最后一行是FROM Cash_Flow_Statements AS s 。 当我从原始帖子中将变量公式插入到现有SQL语句中时，代码为FROM (Income_Statements AS Income_Statements _ INNER JOIN Balance_Sheets AS Balance_Sheets ON (Income_Statements.Ticker = Balance_Sheets.Ticker) AND (Income_Statements.[Year] = Balance_Sheets.[Year]) AND (Income_Statements.Period = Balance_Sheets.Period)) _ INNER JOIN Cash_Flow_Statements AS Cash_Flow_Statements ON (Balance_Sheets.Ticker = Cash_Flow_Statements.Ticker) AND (Balance_Sheets.[Year] = Cash_Flow_Statements.[Year]) AND (Balance_Sheets.Period = Cash_Flow_Statements.Period) 。 我几乎肯定这是问题所在，但不知道如何解决。

Answer 1

让我们不要太专心致志，让我们集中精力选择合适的行。

假设我们有一个名为[SalesSummary]的表，其中包含

Item      FiscalYear  Quarter  TotalSales
--------  ----------  -------  ----------
bicycles        2011        1         100
bicycles        2011        2         200
bicycles        2011        3         300
bicycles        2011        4         400
bicycles        2012        1         500
bicycles        2012        2         600
bicycles        2012        3         700
bicycles        2012        4         800
ham             2011        1          10
ham             2011        2          20
ham             2011        3          30
ham             2011        4          40
ham             2012        1          50
ham             2012        2          60
ham             2012        3          70
ham             2012        4          80

如果我们要创建一个查询，以显示季度数字以及过去12个月（当前季度加上前三个季度）的总销售额，则可能会认为我们必须开始弄乱IIf()来处理“从一个FiscalYear到下一个。 幸运的是，我们没有这样做，因为我们可以在下一个财政年度仅复制带有“假”季度的相同数据：2011_Q（4）变为2012_Q（0），2011_Q（3）变为2012_Q（-1），依此类推。

    SELECT
        Item,
        FiscalYear,
        Quarter,
        TotalSales
    FROM SalesSummary
UNION ALL
    SELECT
        Item,
        FiscalYear + 1,
        Quarter - 4,
        TotalSales
    FROM SalesSummary

回报

Item      FiscalYear  Quarter  TotalSales
--------  ----------  -------  ----------
bicycles        2011        1         100
bicycles        2011        2         200
bicycles        2011        3         300
bicycles        2011        4         400
bicycles        2012        1         500
bicycles        2012        2         600
bicycles        2012        3         700
bicycles        2012        4         800
ham             2011        1          10
ham             2011        2          20
ham             2011        3          30
ham             2011        4          40
ham             2012        1          50
ham             2012        2          60
ham             2012        3          70
ham             2012        4          80
bicycles        2012       -3         100
bicycles        2012       -2         200
bicycles        2012       -1         300
bicycles        2012        0         400
bicycles        2013       -3         500
bicycles        2013       -2         600
bicycles        2013       -1         700
bicycles        2013        0         800
ham             2012       -3          10
ham             2012       -2          20
ham             2012       -1          30
ham             2012        0          40
ham             2013       -3          50
ham             2013       -2          60
ham             2013       -1          70
ham             2013        0          80

如果我们将该查询另存为[SalesUnion]，则可以使用它来生成总计

SELECT 
    Item,
    FiscalYear,
    Quarter,
    TotalSales,
    (
        SELECT 
            SUM(su.TotalSales) 
            FROM SalesUnion su 
            WHERE su.Item = s.Item 
                AND su.FiscalYear = s.FiscalYear 
                AND (su.Quarter Between s.Quarter - 3 And s.Quarter)
    ) AS SalesLast12Months
FROM SalesSummary s

或者，如果您不想依赖保存的查询，则可以一次完成所有操作：

SELECT 
    Item,
    FiscalYear,
    Quarter,
    TotalSales,
    (
        SELECT 
            SUM(su.TotalSales) 
            FROM 
                (
                        SELECT
                            Item,
                            FiscalYear,
                            Quarter,
                            TotalSales
                        FROM SalesSummary
                    UNION ALL
                        SELECT
                            Item,
                            FiscalYear + 1,
                            Quarter - 4,
                            TotalSales
                        FROM SalesSummary
                ) su 
            WHERE su.Item = s.Item 
                AND su.FiscalYear = s.FiscalYear 
                AND (su.Quarter Between s.Quarter - 3 And s.Quarter)
    ) AS SalesLast12Months
FROM SalesSummary s

无论哪种方式，结果都是

Item      FiscalYear  Quarter  TotalSales  SalesLast12Months
--------  ----------  -------  ----------  -----------------
bicycles        2011        1         100                100
bicycles        2011        2         200                300
bicycles        2011        3         300                600
bicycles        2011        4         400               1000
bicycles        2012        1         500               1400
bicycles        2012        2         600               1800
bicycles        2012        3         700               2200
bicycles        2012        4         800               2600
ham             2011        1          10                 10
ham             2011        2          20                 30
ham             2011        3          30                 60
ham             2011        4          40                100
ham             2012        1          50                140
ham             2012        2          60                180
ham             2012        3          70                220
ham             2012        4          80                260

Answer 2

变量Formula应包含以下内容：

SELECT (SUM(su.Net_Cash_Flow_Operating) - SUM(su.Capital_Expenditures)) FROM (SELECT Ticker, [Year], Period, Net_Cash_Flow_Operating, Capital_Expenditures FROM Cash_Flow_Statements UNION ALL SELECT Ticker, [Year] + 1, Period - 4, Net_Cash_Flow_Operating, Capital_Expenditures FROM Cash_Flow_Statements) su WHERE su.Ticker = c.Ticker AND su.[Year] = c.[Year] AND (su.Period Between c.Period - 3 And c.Period)