Question

我正在使用SQL-Server，并有一张我的采购订单（库存）的表格。但是当我试图以最新成本价格和最新销售价格来获取所有可用股票时，我坚持查询。

我查询它运行成功，但我需要一些更好和优化的方法来执行此操作，因为当表有n个记录时，它会变慢。

查询示例：

SELECT 
    po.ProductID, sum(po.AvailableQty) as AvailableQty,
    (select top 1 po2.CostPrice from Sales_PurchaseOrders po2 where po2.PurchasedAt=max(po.PurchasedAt)) as CostPrice,
    (select top 1 po2.SellingPrice from Sales_PurchaseOrders po2 where po2.PurchasedAt=max(po.PurchasedAt)) as SellingPrice
FROM 
    Sales_PurchaseOrders po
INNER JOIN Sales_Products p on p.ProductID=po.ProductID
GROUP BY po.ProductID

表格数据

PurchaseOrderID ProductID   CostPrice                               SellingPrice                            AvailableQty                            PurchasedAt
--------------- ----------- --------------------------------------- --------------------------------------- --------------------------------------- -----------------------
1               1           90.000000                               100.000000                              2.000000                                2016-07-28 00:00:00.000
2               1           33.580000                               50.000000                               0.000000                                2016-06-28 00:00:00.000
3               2           200.000000                              240.000000                              15.000000                               2016-07-30 00:00:00.000
4               1           50.000000                               60.000000                               0.000000                                2016-08-02 00:00:00.000
5               1           50.000000                               60.000000                               1.000000                                2016-08-03 00:00:00.000
6               1           100.000000                              110.000000                              6.000000                                2016-08-04 00:00:00.000
7               1           25.000000                               30.000000                               3.000000                                2016-08-03 00:00:00.000
8               1           20.000000                               30.000000                               0.000000                                2016-07-30 00:00:00.000
1007            1           100.000000                              200.000000                              2.000000                                2016-09-24 00:00:00.000

查询结果：

ProductID   AvailableQty                            CostPrice                               SellingPrice
----------- --------------------------------------- --------------------------------------- ---------------------------------------
1           14.000000                               100.000000                              200.000000
2           15.000000                               200.000000                              240.000000

可以通过某种聚合函数，或任何其他更好的优化方式来执行此操作。

谢谢，

Answer 1

我认为这可以满足您的需求：

SELECT po.ProductID, sum(po.AvailableQty) as AvailableQty,
       MAX(last_CostPrice), MAX(last_SellingPrice)
FROM (SELECT po.*, 
             FIRST_VALUE(CostPrice) OVER (PARTITION BY ProductId ORDER BY PurchasedAt DESC) as last_CostPrice,
             FIRST_VALUE(SellingPrice) OVER (PARTITION BY ProductId ORDER BY PurchasedAt DESC) as last_SellingPrice
      FROM Sales_PurchaseOrders po
     ) po
GROUP BY po.ProductID;

注意：

查询表Sales_Products似乎完全没必要。
您可能想要产品的最新成本和销售价格，而不是所有产品。
您可以在子查询中使用FIRST_VALUE()来获取此信息。

Answer 2

亲爱的Mehmood试试这个。

;with wt_table 
as
(
select ROW_NUMBER() over(partition by po.ProductID order by PurchasedAt desc) as Num,
AvailableQty=sum(po.AvailableQty) over(partition by po.ProductID),
po.ProductID,
po.CostPrice,
po.SellingPrice,
po.PurchasedAt
From    #Sales_PurchaseOrders po)
select * from wt_table  where Num=1

Answer 3

试试这个：

with Sales_PurchaseOrders(PurchaseOrderID,ProductID,CostPrice,SellingPrice,AvailableQty,PurchasedAt)AS(
select 1,1,90.000000,100.000000,2.000000,'2016-07-28 00:00:00.000' union all
select 2,1,33.580000,50.000000,0.000000,'2016-06-28 00:00:00.000' union all
select 3,2,200.000000,240.000000,15.000000,'2016-07-30 00:00:00.000' union all
select 4,1,50.000000,60.000000,0.000000,'2016-08-02 00:00:00.000' union all
select 5,1,50.000000,60.000000,1.000000,'2016-08-03 00:00:00.000' union all
select 6,1,100.000000,110.000000,6.000000,'2016-08-04 00:00:00.000' union all
select 7,1,25.000000,30.000000,3.000000,'2016-08-03 00:00:00.000' union all
select 8,1,20.000000,30.000000,0.000000,'2016-07-30 00:00:00.000' union all
select 1007,1,100.000000,200.000000,2.000000,'2016-09-24 00:00:00.000'
)
select * from (
    SELECT 
po.ProductID, sum(po.AvailableQty)over(partition by po.ProductID) as AvailableQty,CostPrice,SellingPrice,
row_number()over(partition by po.ProductID order by po.PurchasedAt desc) as seq
    FROM  Sales_PurchaseOrders  po

) as t where t.seq=1

    ProductID   AvailableQty    CostPrice   SellingPrice    seq
1   1   14,000000   100,000000  200,000000  1
2   2   15,000000   200,000000  240,000000  1

自我加入聚合函数或更好的方法

3 个答案: