Sql ginDate，#Temp.EndDate）作为总天数， parts.count+1作为GroupCnt， dim_number.id+1作为GroupNum 从…起 #临时工 交叉应用 （选择DATEDIFF（DAY、#Temp.BeginDate、#T

ginDate，#Temp.EndDate）作为总天数， parts.count+1作为GroupCnt， dim_number.id+1作为GroupNum 从…起 #临时工 交叉应用 （选择DATEDIFF（DAY、#Temp.BeginDate、#Temp.EndDate）/#Temp.GroupBy作为计数）作为部分 内连接 dim_编号 在dim_number.id>=0上

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dim_number.id第一个解决方案非常简洁。谢谢现在我要明白了…哈哈。至于第二个解决方案，我得到EndDate=BeginDate。你得到了同样的答案吗？第一个解决方案非常简单。谢谢现在我要明白了…哈哈。至于第二个解决方案，我得到EndDate=BeginDate。你得到了同样的答案吗？谢谢@Mattballie提供的这个解决方案……尽管我必须说，我需要一段时间才能理解这里发生了什么。：）感谢@Mattballie提供的这个解决方案……尽管我必须说，我需要一段时间才能理解这里发生的事情。：）

CREATE TABLE #Temp (ID INT Identity(1,1) Primary Key, BeginDate datetime, EndDate datetime, GroupBy INT)
INSERT INTO #Temp
SELECT '2015-06-05 00:00:00.000','2015-06-12 00:00:00.000',7
UNION
SELECT '2015-06-05 00:00:00.000', '2015-06-08 00:00:00.000',7
UNION
SELECT '2015-10-22 00:00:00.000', '2015-10-31 00:00:00.000',7

SELECT *, DATEDIFF(DAY,BeginDate, EndDate) TotalDays FROM #Temp
DROP TABLE #Temp

ID  BeginDate       EndDate         GroupBy     TotalDays
1   6/5/15 0:00     6/8/15 0:00     7           3
2   6/5/15 0:00     6/12/15 0:00    7           7
3   10/22/15 0:00   10/31/15 0:00   7           9

ID  BeginDate       EndDate         GroupBy TotalDays   GroupCnt    GroupNum
1   6/5/15 0:00     6/8/15 0:00     7       3           1           1
2   6/5/15 0:00     6/12/15 0:00    7       7           1           1
3   10/22/15 0:00   10/29/15 0:00   7       9           2           1
3   10/29/15 0:00   10/31/15 0:00   7       9           2           2

GroupCNT = how many records there're of the grouped records after applying the above records.

SELECT DISTINCT
  ID
, BeginDate
, EndDate
, GroupBy
, DATEDIFF(DAY,BeginDate, EndDate) TotalDays
, CAST(GroupBy as decimal(18,6))%CAST(DATEDIFF(DAY,BeginDate, EndDate) AS decimal(18,6)) Modulus
, CASE WHEN DATEDIFF(DAY,BeginDate, EndDate) <= GroupBy THEN BeginDate END NewBeginDate
, CASE WHEN DATEDIFF(DAY,BeginDate, EndDate) <= GroupBy THEN EndDate END NewEndDate
FROM #Temp

;WITH cte AS (
    SELECT  ID,
            BeginDate,
            EndDate,
            GroupBy, 
            DATEDIFF(DAY, BeginDate, EndDate) AS TotalDays, 
            1 AS GroupNum 
    FROM    #Temp
    UNION ALL 
    SELECT  ID,
            BeginDate,
            EndDate,
            GroupBy,
            TotalDays,
            GroupNum + 1
    FROM    cte
    WHERE   GroupNum * GroupBy < TotalDays
)
SELECT  ID,
        BeginDate = CASE WHEN GroupNum = 1 THEN BeginDate 
                         ELSE DATEADD(DAY, GroupBy * (GroupNum - 1), BeginDate)
                         END ,
        EndDate   = CASE WHEN TotalDays <= GroupBy THEN EndDate
                         WHEN DATEADD(DAY, GroupBy * GroupNum, BeginDate) > EndDate THEN EndDate
                         ELSE DATEADD(DAY, GroupBy * GroupNum, BeginDate)
                         END ,
        GroupBy,
        TotalDays,
        COUNT(*) OVER (PARTITION BY ID) GroupCnt,
        GroupNum
FROM    cte
OPTION (MAXRECURSION 0)

ID          BeginDate               EndDate                 GroupBy     TotalDays   GroupNum
----------- ----------------------- ----------------------- ----------- ----------- -----------
1           2015-06-05 00:00:00.000 2015-06-08 00:00:00.000 7           3           1
2           2015-06-05 00:00:00.000 2015-06-12 00:00:00.000 7           7           1
3           2015-10-22 00:00:00.000 2015-10-31 00:00:00.000 7           9           1
3           2015-10-22 00:00:00.000 2015-10-31 00:00:00.000 7           9           2

ID          BeginDate               EndDate                 GroupBy     TotalDays   GroupCnt    GroupNum
----------- ----------------------- ----------------------- ----------- ----------- ----------- -----------
1           2015-06-05 00:00:00.000 2015-06-08 00:00:00.000 7           3           1           1
2           2015-06-05 00:00:00.000 2015-06-12 00:00:00.000 7           7           1           1
3           2015-10-22 00:00:00.000 2015-10-29 00:00:00.000 7           9           2           1
3           2015-10-29 00:00:00.000 2015-10-31 00:00:00.000 7           9           2           2

;WITH cte AS (
    SELECT  ID,
            BeginDate,
            EndDate,
            GroupBy, 
            DATEDIFF(DAY, BeginDate, EndDate) AS TotalDays, 
            1 AS GroupNum 
    FROM    #Temp
    UNION ALL 
    SELECT  ID,
            BeginDate,
            EndDate,
            GroupBy,
            TotalDays,
            GroupNum + 1
    FROM    cte
    WHERE   GroupNum * GroupBy < TotalDays
)

SELECT  ID,
        BeginDate = COALESCE(LAG(BeginDate) OVER (PARTITION BY ID ORDER BY GroupNum) + GroupBy * (GroupNum - 1), BeginDate),
        EndDate   = COALESCE(LEAD(BeginDate) OVER (PARTITION BY ID ORDER BY GroupNum) + GroupBy * GroupNum, EndDate),
        GroupBy,
        TotalDays,
        COUNT(*) OVER (PARTITION BY ID) GroupCnt,
        GroupNum
FROM    cte
OPTION (MAXRECURSION 0)

CREATE TABLE dim_number (id INT);
INSERT INTO dim_number VALUES ((0), (1), (2), (3)); -- Populate this to a large number

SELECT
    #Temp.Id,
    CASE WHEN dim_number.id = 0
         THEN #Temp.BeginDate
         ELSE DATEADD(DAY,  dim_number.id      * #Temp.GroupBy, #Temp.BeginDate)
    END                                                             AS BeginDate,
    CASE WHEN dim_number.id = parts.count
         THEN #Temp.EndDate
         ELSE DATEADD(DAY, (dim_number.id + 1) * #Temp.GroupBy, #Temp.BeginDate)
    END                                                             AS EndDate,
    #Temp.GroupBy                                                   AS GroupBy,
    DATEDIFF(DAY, #Temp.BeginDate, #Temp.EndDate)                   AS TotalDays,
    parts.count + 1                                                 AS GroupCnt,
    dim_number.id + 1                                               AS GroupNum
FROM
    #Temp
CROSS APPLY
    (SELECT DATEDIFF(DAY, #Temp.BeginDate, #Temp.EndDate) / #Temp.GroupBy AS count)   AS parts
INNER JOIN
    dim_number
        ON  dim_number.id >= 0
        AND dim_number.id <= parts.count