Sql Server 中的计算 [英] Calculation in Sql Server

问题描述

我尝试执行以下计算

示例数据:

CREATE TABLE #Table1
  (
     rno   int identity(1,1),
     ccp   varchar(50),
     [col1] INT,
     [col2] INT,
     [col3] INT,
     col4 as [col2]/100.0
  );

INSERT INTO #Table1
            (ccp,[col1],[col2],[col3])
VALUES      ('ccp1',15,10,1100),
            ('ccp1',20,10,1210),
            ('ccp1',30,10,1331),
            ('ccp2',10,15,900),
            ('ccp2',15,15,1000),
            ('ccp2',20,15,1010)

+-----+------+------+------+------+----------+
| rno | ccp  | col1 | col2 | col3 |   col4   |
+-----+------+------+------+------+----------+
|   1 | ccp1 |   15 |   10 | 1100 | 0.100000 |
|   2 | ccp1 |   20 |   10 | 1210 | 0.100000 |
|   3 | ccp1 |   30 |   10 | 1331 | 0.100000 |
|   4 | ccp2 |   10 |   15 |  900 | 0.150000 |
|   5 | ccp2 |   15 |   15 | 1000 | 0.150000 |
|   6 | ccp2 |   20 |   15 | 1010 | 0.150000 |
+-----+------+------+------+------+----------+

注意:不仅仅是3条记录，每个ccp可以有N条记录

Note : It is not just 3 records each ccp can have N no.of records

预期结果:

1083.500000 --1100 - (15 * (1+0.100000))
1169.850000 --1210 - ((20 * (1+0.100000)) + (15 * (1+0.100000)* (1+0.100000)) )
1253.835000 --1331 - ((30 * (1+0.100000)) + (20 * (1+0.100000)* (1+0.100000)) + (15 * (1+0.100000)* (1+0.100000) *(1+0.100000)) )
888.500000  --900 - (10 * (1+0.150000))
969.525000  --1000 - ((15 * (1+0.150000)) + (10 * (1+0.150000)* (1+0.150000)) )
951.953750  --1010 - ((20 * (1+0.150000)) + (15 * (1+0.150000)* (1+0.150000)) + (10 * (1+0.150000)* (1+0.150000) *(1+0.150000)) )

我知道我们可以使用递归 CTE 来做到这一点，但效率不高，因为我必须对超过 500 万条记录执行此操作.

I know we can do this using Recursive CTE, it is not efficient since i have to do this for more than 5 million records.

我希望实现类似这种基于集合的方法

I am looking to implement something like this set based approach

对于 ccp : ccp1

SELECT col3 - ( col1 * ( 1 + col4 ) )
FROM   #Table1
WHERE  rno = 1

SELECT rno,
       col3 - ( ( col1 * Power(( 1 + col4 ), 1) ) + ( Lag(col1, 1)
                                                        OVER(
                                                          ORDER BY rno ) * Power(( 1 + col4 ), 2) ) )
FROM   #Table1
WHERE  rno IN ( 1, 2 )

SELECT rno,
       col3 - ( ( col1 * Power(( 1 + col4 ), 1) ) + ( Lag(col1, 1)
                                                        OVER(
                                                          ORDER BY rno ) * Power(( 1 + col4 ), 2) ) + ( Lag(col1, 2)
                                                                                                          OVER(
                                                                                                            ORDER BY rno ) * Power(( 1 + col4 ), 3) ) )
FROM   #Table1
WHERE  rno IN ( 1, 2, 3 ) 

有没有办法在单个查询中计算?

Is there a way to calculate in single query?

仍然愿意接受建议.我坚信应该有一些使用 SUM () Over(Order by) 窗口聚合函数来做到这一点.

Still am open to suggestions. I strongly beleive there should be some to do this using SUM () Over(Order by) window aggregate function.

推荐答案

self join 的方法.不确定这是否比使用 cross apply 的版本更有效.

An approach with a self join. Not sure if this would be any more efficient than your version with cross apply.

WITH T AS
  (SELECT *,
          ROW_NUMBER() OVER(PARTITION BY CCP
                            ORDER BY RNO) AS RN
   FROM #TABLE1)
SELECT T1.RNO,
       T1.CCP,
       T1.COL1,
       T1.COL2,
       T1.COL3,
       T1.COL3-SUM(T2.COL1*POWER(1+T1.COL2/100.0,T1.RN-T2.RN+1)) AS RES
FROM T T1
JOIN T T2 ON T1.CCP=T2.CCP
AND T1.RN>=T2.RN
GROUP BY T1.RNO,
         T1.CCP,
         T1.COL1,
         T1.COL2,
         T1.COL3

示例演示

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