Sql server 谢谢@Nizam的回答。关于查询性能，您能说些什么呢？因为它在存储过程中会被调用数千次，并且每次更新时更新的表大约有15000行（它将是一个临时表）。我不太擅长阅读执行计划。谢谢@Nizam的回答。关于查询性能，您能说些什么呢？因为它在存储过程中会被调用数

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谢谢@Nizam的回答。关于查询性能，您能说些什么呢？因为它在存储过程中会被调用数千次，并且每次更新时更新的表大约有15000行（它将是一个临时表）。我不太擅长阅读执行计划。谢谢@Nizam的回答。关于查询性能，您能说些什么呢？因为它在存储过程中会被调用数千次，并且每次更新时更新的表大约有15000行（它将是一个临时表）。我不太擅长阅读执行计划。

Date           Cnt   Val  Cumulative  IsLastDate
................................................
2014-01-01     1     5    0           0
2014-01-02     1     100  0           0
2014-01-03     1     300  0           0
2014-01-04     1     300  800         1
2014-01-05     1     10   0           0
2014-01-06     1     50   0           0
2014-01-07     1     50   0           0
2014-01-08     1     150  500         1
2014-01-01     2     5    0           0
2014-01-02     2     20   0           0
2014-01-03     2     50   0           0
2014-01-04     2     100  300         1
2014-01-05     2     5    0           0
2014-01-06     2     20   0           0
2014-01-07     2     5    0           0
2014-01-08     2     10   100         1

Date           Cnt   Val  Cumulative  IsLastDate
................................................
2014-01-01     1     5    100         0
2014-01-02     1     100  200         0
2014-01-03     1     300  500         0
2014-01-04     1     300  800         1
2014-01-05     1     10   250         0
2014-01-06     1     50   300         0
2014-01-07     1     50   350         0
2014-01-08     1     150  500         1
2014-01-01     2     5    130         0
2014-01-02     2     20   150         0
2014-01-03     2     50   200         0
2014-01-04     2     100  300         1
2014-01-05     2     5    65          0
2014-01-06     2     20   85          0
2014-01-07     2     5    90          0
2014-01-08     2     10   100         1

UPDATE T 
SET T.Cumulative = TT.Cumulative - TT.Val
FROM T INNER JOIN T TT ON
TT.[Date] = DATEADD(DAY,1,T.[Date]) AND TT.Cnt = T.Cnt AND T.IsLastDate <> 1

UPDATE YourTable
SET Cumulative = z.NewCumulative
FROM (
    SELECT *,
            SUM(Cumulative - val) OVER (PARTITION BY GroupPartition ORDER BY Date DESC)AS NewCumulative
    FROM (
        SELECT *, 
               SUM(CAST(IsLastDate AS Int)) OVER (ORDER BY Date DESC) GroupPartition
        FROM YourTable
        )Z
    )Z

WHERE YourTable.Date = Z.Date

SUM(CAST(IsLastDate AS Int)) OVER (ORDER BY Date DESC) GroupPartition

SUM(Cumulative - val) OVER (PARTITION BY GroupPartition ORDER BY Date DESC)AS NewCumulative

WITH TBL AS (

SELECT T.*, 
       CASE WHEN 
         ROW_NUMBER() OVER (PARTITION BY T.CNT, LAST_DATE ORDER BY T.DATE) =1 
       THEN 0
       ELSE T.VAL
       END VAL_ADJ,
       LAST_DATE
FROM T

CROSS APPLY (
   select MAX(TE.DATE)
   FROM T TE 
   WHERE TE.[Date] < T.[Date] 
   AND TE.Cnt = T.Cnt 
   AND TE.IsLastDate = 1
) D(LAST_DATE)

), RESULT AS (

SELECT 
  A.DATE, 
  A.CNT, 
  A.VAL, 
  SUM(B.VAL_ADJ) + TOTAL_FULL - TOTAL CUMULATIVE, 
  A.ISLASTDATE
FROM  TBL A

CROSS APPLY (
   select SUM(VAL_ADJ)
   FROM TBL 
   WHERE ISNULL(LAST_DATE,0) = ISNULL(A.LAST_DATE,0) AND CNT = A.CNT
   GROUP BY CNT, LAST_DATE
) N(TOTAL)

CROSS APPLY (
   select MAX(CUMULATIVE)
   FROM TBL 
   WHERE ISNULL(LAST_DATE,0) = ISNULL(A.LAST_DATE,0) AND CNT = A.CNT
   GROUP BY CNT, LAST_DATE
) L(TOTAL_FULL)

LEFT JOIN TBL B
   ON A.DATE >= B.DATE
   AND A.CNT = B.CNT
   AND ISNULL(A.LAST_DATE,0) = ISNULL(B.LAST_DATE,0)

GROUP BY  A.DATE, A.CNT, A.VAL, A.ISLASTDATE, A.LAST_DATE, N.TOTAL, TOTAL_FULL

 )

UPDATE T
  SET CUMULATIVE = B.CUMULATIVE
FROM T A
INNER JOIN RESULT B
   ON A.CNT = B.CNT
   AND A.DATE = B.DATE

SELECT * FROM T

UPDATE T
   SET CUMULATIVE = NewCumulative
FROM T
INNER JOIN (
    SELECT *,            
          SUM(Z.Cumulative - case when linha = 1 then 0 else VAL_ANT end) OVER (PARTITION BY GroupPartition ORDER BY Z.Date DESC) AS NewCumulative
    FROM (
       SELECT Z.*, ROW_NUMBER() OVER(PARTITION BY GroupPartition ORDER BY Z.DATE DESC) LINHA, IsNull(T0.VAL,0) VAL_ANT
       FROM (
           SELECT *, 
               SUM(CAST(IsLastDate AS Int)) OVER (ORDER BY CNT, Date DESC) GroupPartition
           FROM T
       )Z
       LEFT JOIN T T0
         on T0.DATE = DATEADD(DAY,1,Z.DATE)
         and T0.CNT = Z.CNT
    ) Z 

) Z
ON T.Date = Z.Date AND T.CNT = Z.CNT

SELECT *
FROM T
ORDER BY CNT, DATE

SELECT M.[Date],M.Cnt,M.Val,
Cumulative = 
    CASE (M.IsLastDate) WHEN 1 THEN M.Cumulative
    ELSE ((SELECT TOP(1) Cumulative FROM T WHERE [Date] > M.[Date] AND Cnt = M.Cnt 
        AND IsLastDate = 1) 
    - 
    (SELECT SUM(Val) FROM T B WHERE B.[Date] > M.[Date] 
        AND M.Cnt = B.Cnt 
        AND B.[Date] <= (SELECT TOP(1) [Date] FROM T WHERE [Date] > M.[Date] 
            AND Cnt = M.Cnt AND IsLastDate = 1))
    )
    END,
M.IsLastDate
 FROM T M
 ORDER BY CNT,[Date] ,IsLastDate%1 --Just for viewing in an ordered way