复杂滚动场景（CROSS APPLY和OUTER APPLY示例）

Question

我目前有以下数据（但更大！）

/*--:::::::::::
DROP TABLE #target
DROP TABLE #Fact
*/--:::::::::::
CREATE TABLE #target 
    (
    PlayerKey INT,
    Name            VARCHAR(8),
    LiveKey     INT
    );
INSERT INTO #target 
    values
    (1,'michael',20130103),
    (2,'jackson',20130107);

CREATE TABLE #Fact 
    (
    DateKey     INT,
    PlayerKey INT,
    Amount      INT
    );
INSERT INTO #Fact 
    values
    (20130101,1,10),
    (20130102,1,90),
    (20130103,1,18),
    (20130103,2,79),
    (20130103,3,99),
    (20130104,2,15),
    (20130105,1,12),
    (20130105,2,15),
    (20130106,1,60),
    (20130107,1,96),
    (20130107,2,88),
    (20130107,4,28),
    (20130108,1,13),
    (20130108,2,15),
    (20130109,1,33),
    (20130109,2,67),
    (20130110,1,19),
    (20130110,2,17)
    ;

查询的开头如下。

DECLARE @NumDays INT = 3;

WITH    basic_cte AS
        (
        SELECT  rn = ROW_NUMBER() OVER(PARTITION BY d.Name ORDER BY f.DateKey),
                f.DateKey,
                d.Name,
                f.Amount
        FROM    #Fact f
                INNER JOIN #target d ON
                  f.PlayerKey = d.PlayerKey AND
                  f.DateKey >= d.LiveKey AND
                  f.DateKey < CONVERT(CHAR(8),CONVERT(DATETIME,CONVERT(DATETIME,CONVERT(CHAR(8),d.LiveKey,112))+@NumDays),112)
        )
SELECT  x.*,
        "RollingAmount" = SUM(Amount) OVER(PARTITION BY Name ORDER BY DateKey)
FROM    basic_cte x;

这给出了以下内容：

假设我们有DimDate制作视图可用，如何确保michael的{​​{1}}行的数量为0？

也可以在同一个脚本中添加新的“AmountAll”和“AmountAllRolling”列，这些列可以为所有玩家提供数字，包括PlayerKeys 3和4？我猜这会涉及将20130104更改为INNER JOIN？

因此，鉴于上述情况，最终结果如下：

---

编辑

通过波格丹的所有出色帮助，我得到了以下内容 我添加了额外的AmountGroup总数，这是指定玩家的总数 - 这只是“很好”而不是原始规范的一部分。

LEFT OUTER JOIN

Answer 1

我假设您有一个具有以下结构的DimDate表：

CREATE TABLE DimDate
(
DateKey INT PRIMARY KEY
);

和DateKey列没有差距。

解决方案：

DECLARE @NumDays INT = 3;

WITH    basic_cte AS
        (
            SELECT  x.DateKey,
                    d.Name,
                    Amount = ISNULL(f.Amount,0)
            FROM    
            (
                SELECT  t.*, CONVERT(INT,CONVERT(CHAR(8),CONVERT(DATETIME,CONVERT(DATETIME,CONVERT(CHAR(8),t.LiveKey,112))+@NumDays),112)) AS EndLiveKey
                FROM    #target t
            ) d 
            CROSS APPLY
            (
                SELECT  dm.DateKey
                FROM    DimDate dm
                WHERE   dm.DateKey >= d.LiveKey 
                AND     dm.DateKey < d.EndLiveKey           
            ) x
            LEFT OUTER JOIN #Fact f 
            ON f.PlayerKey = d.PlayerKey 
            AND f.DateKey = x.DateKey
        )
SELECT  rn = ROW_NUMBER() OVER(PARTITION BY Name ORDER BY DateKey),
        y.*,
        "RollingAmount" = SUM(Amount) OVER(PARTITION BY Name ORDER BY DateKey)
FROM    basic_cte y;

编辑＃1：

DECLARE @NumDays INT = 3;

WITH    basic_cte AS
        (
            SELECT  rn = ROW_NUMBER() OVER(PARTITION BY Name ORDER BY x.DateKey),
                    x.DateKey,
                    d.Name,
                    Amount      = ISNULL(f.Amount,0),
                    AmountAll   = ISNULL(fall.AmountAll,0)
            FROM    
            (
                SELECT  t.*, CONVERT(INT,CONVERT(CHAR(8),CONVERT(DATETIME,CONVERT(DATETIME,CONVERT(CHAR(8),t.LiveKey,112))+@NumDays),112)) AS EndLiveKey
                FROM    #target t
            ) d 
            CROSS APPLY
            (
                SELECT  dm.DateKey
                FROM    DimDate dm
                WHERE   dm.DateKey >= d.LiveKey 
                AND     dm.DateKey < d.EndLiveKey           
            ) x
            OUTER APPLY
            (
                SELECT  SUM(fct.Amount) AS Amount
                FROM    #Fact fct 
                WHERE   fct.DateKey = x.DateKey
                AND     fct.PlayerKey = d.PlayerKey
            ) f
            OUTER APPLY
            (
                SELECT  SUM(fct.Amount) AS AmountAll 
                FROM    #Fact fct 
                WHERE   fct.DateKey = x.DateKey
            ) fall
        )
SELECT  
        y.*,
        "RollingAmount"     = SUM(Amount) OVER(PARTITION BY Name ORDER BY DateKey),
        "RollingAmountAll"  = SUM(AmountAll) OVER(PARTITION BY Name ORDER BY DateKey)
FROM    basic_cte y;

编辑＃2：

DECLARE @NumDays INT = 3;

WITH    basic_cte AS
        (
            SELECT  rn = ROW_NUMBER() OVER(PARTITION BY Name ORDER BY x.DateKey),
                    x.DateKey,
                    d.Name,
                    Amount      = ISNULL(f.Amount,0),
                    AmountAll   = ISNULL(f.AmountAll,0)
            FROM    
            (
                SELECT  t.*, EndLiveKey = CONVERT(INT,CONVERT(CHAR(8),CONVERT(DATETIME,CONVERT(DATETIME,CONVERT(CHAR(8),t.LiveKey,112))+@NumDays),112))
                FROM    #target t
            ) d 
            CROSS APPLY
            (
                SELECT  dm.DateKey
                FROM    DimDate dm
                WHERE   dm.DateKey >= d.LiveKey 
                AND     dm.DateKey < d.EndLiveKey           
            ) x
            OUTER APPLY
            (
                SELECT  AmountAll   = SUM(fbase.Amount),
                        Amount      = SUM(CASE WHEN PlayerKey1 = PlayerKey2 THEN fbase.Amount END)
                FROM
                (
                    SELECT  fct.Amount, fct.PlayerKey AS PlayerKey1, d.PlayerKey AS PlayerKey2
                    FROM    #Fact fct 
                    WHERE   fct.DateKey = x.DateKey
                ) fbase
            ) f
        )
SELECT  
        y.*,
        "RollingAmount"     = SUM(Amount) OVER(PARTITION BY Name ORDER BY DateKey),
        "RollingAmountAll"  = SUM(AmountAll) OVER(PARTITION BY Name ORDER BY DateKey)
FROM    basic_cte y;