ParaellePeriod 函数允许比较时间点之间的值（销售额与一年前相比如何）。我在使用它时做错了什么，但不知道那可能是什么。
设置
我创建了一个简单的 PowerPivot SQL Server 2008+ 源查询并将其命名为 Source。该查询生成 168 行：6 个 ID (100-600) 和 28 个日期（从 2010 年 1 月到 2012 年 4 月的一个月的第一天）全部交叉应用在一起。
; WITH SRC (groupKey, eventDate, value) AS
(
SELECT G.groupKey, D.eventDate, CAST(rand(G.groupKey * year(D.eventDate) * month(D.eventDate)) * 100 AS int)
FROM
(
SELECT 100
UNION ALL SELECT 200
UNION ALL SELECT 300
UNION ALL SELECT 400
UNION ALL SELECT 500
UNION ALL SELECT 600
) G (groupKey)
CROSS APPLY
(
SELECT CAST('2010-01-01' AS date)
UNION ALL SELECT CAST('2010-02-01' AS date)
UNION ALL SELECT CAST('2010-03-01' AS date)
UNION ALL SELECT CAST('2010-04-01' AS date)
UNION ALL SELECT CAST('2010-05-01' AS date)
UNION ALL SELECT CAST('2010-06-01' AS date)
UNION ALL SELECT CAST('2010-07-01' AS date)
UNION ALL SELECT CAST('2010-08-01' AS date)
UNION ALL SELECT CAST('2010-09-01' AS date)
UNION ALL SELECT CAST('2010-10-01' AS date)
UNION ALL SELECT CAST('2010-11-01' AS date)
UNION ALL SELECT CAST('2010-12-01' AS date)
UNION ALL SELECT CAST('2011-01-01' AS date)
UNION ALL SELECT CAST('2011-02-01' AS date)
UNION ALL SELECT CAST('2011-03-01' AS date)
UNION ALL SELECT CAST('2011-04-01' AS date)
UNION ALL SELECT CAST('2011-05-01' AS date)
UNION ALL SELECT CAST('2011-06-01' AS date)
UNION ALL SELECT CAST('2011-07-01' AS date)
UNION ALL SELECT CAST('2011-08-01' AS date)
UNION ALL SELECT CAST('2011-09-01' AS date)
UNION ALL SELECT CAST('2011-10-01' AS date)
UNION ALL SELECT CAST('2011-11-01' AS date)
UNION ALL SELECT CAST('2011-12-01' AS date)
UNION ALL SELECT CAST('2012-01-01' AS date)
UNION ALL SELECT CAST('2012-02-01' AS date)
UNION ALL SELECT CAST('2012-03-01' AS date)
UNION ALL SELECT CAST('2012-04-01' AS date)
) D (eventDate)
)
SELECT
*
FROM
SRC;
我使用从 MSDN 中提取的公式在 PowerPivot 中添加了一个派生列
=CALCULATE(SUM(Source[value]), PARALLELPERIOD(Source[eventDate], -1, year))
没有显示错误，但从来没有任何计算数据。我尝试了不同的时间间隔（-1、+1）和周期（年、月），但无济于事。
我能观察到的唯一一点是我的演示和 MSDN 之间的不同之处在于他们为日期定义了一个单独的维度。很容易纠正，所以我用以下内容创建了一个日期查询。此查询为 2010-01-01 和 2012-06-01 之间的所有日期生成一行（1096 行）
DECLARE
@start int = 20100101
, @stop int = 20120601;
WITH L0 AS
(
SELECT
0 AS C
UNION ALL
SELECT
0
)
, L1 AS
(
SELECT
0 AS c
FROM
L0 AS A
CROSS JOIN L0 AS B
)
, L2 AS
(
SELECT
0 AS c
FROM
L1 AS A
CROSS JOIN L1 AS B
)
, L3 AS
(
SELECT
0 AS c
FROM
L2 AS A
CROSS JOIN L2 AS B
)
, L4 AS
(
SELECT
0 AS c
FROM
L3 AS A
CROSS JOIN L3 AS B
)
, L5 AS
(
SELECT
0 AS c
FROM
L4 AS A
CROSS JOIN L4 AS B
)
, NUMS AS
(
SELECT
ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) AS number
FROM
L5
)
, YEARS AS
(
SELECT
Y.number
FROM
NUMS Y
WHERE
Y.number BETWEEN @start / 10000 AND @stop / 10000
)
, MONTHS AS
(
SELECT
Y.number
FROM
NUMS Y
WHERE
Y.number BETWEEN 1 and 12
)
, DAYS AS
(
SELECT
Y.number
FROM
NUMS Y
WHERE
Y.number BETWEEN 1 and 31
)
, CANDIDATES_0 AS
(
SELECT
Y.number * 10000 + M.number * 100 + D.number AS SurrogateKey
, CAST(Y.number * 10000 + M.number * 100 + D.number AS char(8)) AS DateValue
FROM
YEARS Y
CROSS APPLY
MONTHS M
CROSS APPLY
DAYS D
)
, HC AS
(
SELECT
Y.number * 10000 + M.number * 100 + D.number AS SurrogateKey
, CAST(Y.number * 10000 + M.number * 100 + D.number AS char(8)) AS DateValue
FROM
YEARS Y
CROSS APPLY
MONTHS M
CROSS APPLY
DAYS D
WHERE
D.number < 31
AND M.number IN (4,6,9,11)
UNION ALL
SELECT
Y.number * 10000 + M.number * 100 + D.number AS SurrogateKey
, CAST(Y.number * 10000 + M.number * 100 + D.number AS char(8)) AS DateValue
FROM
YEARS Y
CROSS APPLY
MONTHS M
CROSS APPLY
DAYS D
WHERE
D.number < 32
AND M.number IN (1,3,5,7,8,10,12)
UNION ALL
SELECT
Y.number * 10000 + M.number * 100 + D.number AS SurrogateKey
, CAST(Y.number * 10000 + M.number * 100 + D.number AS char(8)) AS DateValue
FROM
YEARS Y
CROSS APPLY
MONTHS M
CROSS APPLY
DAYS D
WHERE
D.number < 29
AND M.number = 2
AND
(
Y.number % 4 > 0
OR Y.number % 100 = 0 AND Y.number % 400 > 0
)
UNION ALL
SELECT
Y.number * 10000 + M.number * 100 + D.number AS SurrogateKey
, CAST(Y.number * 10000 + M.number * 100 + D.number AS char(8)) AS DateValue
FROM
YEARS Y
CROSS APPLY
MONTHS M
CROSS APPLY
DAYS D
WHERE
D.number < 30
AND M.number = 2
AND
(
Y.number % 4 = 0
OR Y.number % 100 = 0 AND Y.number % 400 = 0
)
)
, CANDIDATES AS
(
SELECT
C.SurrogateKey
, CAST(C.DateValue as date) As DateValue
FROM
HC C
WHERE
ISDATE(c.DateValue) = 1
)
, PARTS
(
DateKey
, FullDateAlternateKey
, DayNumberOfWeek
, EnglishDayNameOfWeek
, DayNumberOfMonth
, DayNumberOfYear
, WeekNumberOfYear
, EnglishMonthName
, MonthNumberOfYear
, CalendarQuarter
, CalendarYear
, CalendarSemester
--,FiscalQuarter
--,FiscalYear
--,FiscalSemester
) AS
(
SELECT
CAST(C.SurrogateKey AS int)
, C.DateValue
, DATEPART(WEEKDAY, C.DateValue)
, DATENAME(WEEKDAY, C.DateValue)
, DATEPART(DAY, C.DateValue)
, DATEPART(DAYOFYEAR, C.DateValue)
, DATEPART(WEEK, C.DateValue)
, DATENAME(MONTH, C.DateValue)
, DATEPART(MONTH, C.DateValue)
, DATEPART(QUARTER, C.DateValue)
, DATEPART(YEAR, C.DateValue)
, DATEPART(WEEK, C.DateValue)
FROM
CANDIDATES C
WHERE
C.DateValue IS NOT NULL
)
SELECT
P.*
FROM
--HC P
PARTS P
ORDER BY 1;
生成数据后，我创建了 Source 和 Dates 之间的关系，并尝试了这个公式，但也没有运气
=CALCULATE(SUM(Source[value]), PARALLELPERIOD(Dates[FullDateAlternateKey], -1, year))
PowerPivot 设计器看起来像
对我做错了什么有任何想法吗？