Question

我有下表：

交易记录表

TransactionHistoryId    ProductCode Type    Quantity    PurchasePrice   CurrentPrice
1                       Product1    B       10          3.00            2.00
2                       Product1    B       5           7.00            2.00
3                       Product1    S       -7          7.00            2.00
4                       Product1    S       -8          3.00            3.00
5                       Product1    B       4           10.00           10.00
6                       Product1    B       5           12.00           12.00
8                       Product2    B       8           20.00           20.00

我想获得下表：

TransactionHistoryId    ProductCode Type    Quantity    PurchasePrice   QtyRunning  PriceRunning
1                       Product1    B       10          3.00            10          30.00
2                       Product1    B       5           7.00            15          65.00
3                       Product1    S       -7          7.00            8           65.00
4                       Product1    S       -8          3.00            0           0.00
5                       Product1    B       4           10.00           4           40.00
6                       Product1    B       5           12.00           9           100.00
8                       Product2    B       8           20.00           8           160.00

创建表SQL

IF OBJECT_ID('TEMPDB..#TransactionHistory') IS NOT NULL
DROP TABLE #TransactionHistory
create table #TransactionHistory
(TransactionHistoryId int, 
ProductCode varchar(10),
Type char(1),
Quantity smallint,
PurchasePrice decimal(18,2),
CurrentPrice decimal(18,2)
)
insert into #TransactionHistory
values
(1,'Product1','B',10,3.00,2.00),
(2,'Product1','B',5,7.00,2.00),
(3,'Product1','S',-7,7.00,2.00),
(4,'Product1','S',-8,3.00,3.00),
(5,'Product1','B',4,10.00,10.00),
(6,'Product1','B',5,12.00,12.00),
(8,'Product2','B',8,20.00,20.00)

规则

当运行总量为0时，PriceRunningTotal重置
PriceRunningTotal仅总结Type ='B'（买入），当Type ='S'（已售出）时，保持先前的购买价格总计
请注意，有一个产品2，因此它应该拥有独立于产品1的自己的运行计数

目的

最终找出以下内容的查询：

Product     Quantity       AdjustedPurchasePrice
Product1    9              $11.11
Product2    8              $20

我使用以下SQL Server 2012查询来获取结果，但我觉得它可以做得更好：

查询

SELECT *,   
    PriceRunningTotalFinal = 
    SUM(CASE 
    WHEN QuantityRunningTotal = 0 THEN -1 * PriceRunningTotal
    WHEN Quantity < 0 THEN 0 ELSE PurchasePrice * Quantity END) OVER 
    (
        PARTITION BY ProductCode
        ORDER BY TransactionHistoryId ROWS UNBOUNDED PRECEDING
    )   
FROM (

SELECT TransactionHistoryId, ProductCode, Type,  Quantity, PurchasePrice,  
  QuantityRunningTotal = SUM(Quantity) OVER 
  (
    PARTITION BY ProductCode
    ORDER BY TransactionHistoryId ROWS UNBOUNDED PRECEDING
  ),  
  PriceRunningTotal = SUM(CASE WHEN Quantity < 0 THEN 0 ELSE PurchasePrice * Quantity END) OVER 
  (
    PARTITION BY ProductCode
    ORDER BY TransactionHistoryId ROWS UNBOUNDED PRECEDING
  )       
  FROM TransactionHistory
) AS Results1
ORDER BY ProductCode;

问题

理想情况下，我希望在另一个查询中使用QuantityRunningTotal，但我无法嵌套窗口函数。

任何人都知道更有效的方法来实现这一结果吗？

Answer 1

嗯。我想是这样的：

select th.*,
       sum(case when type = 'B' then Quantity * PurchasePrice
                else 0
           end) over (partition by grp, ProductCode order by TransactionHistoryId
                     ) as PriceRunningTotal
from (select th.*,
             sum(case when running_quantity = 0 then 1 else 0 end) over (partition by ProductCode order by TransactionHistoryId) as grp
      from (select th.*,
                   sum(quantity) over (partition by ProductCode order by TransactionHistoryId
                                      ) as running_quantity
            from TransactionHistory th
           ) th;

我不确定这是否与您的查询逻辑相同。对于此查询：

最里面的子查询计算运行数量。
中间子查询根据运行数量为0的次数计算组。
最外面的查询然后计算运行价格。

SQL在条件上运行完全重置

1 个答案: