计算分层定价的总和。SQL Server。分层定价表

我在SQL Server中的求和查询遇到问题

我有一个像这样的价格表。该表的名称称为TierPricing

CID RangeID MinValue    MaxValue    Price   Class
1   1        1          5           1.50    1
2   2        6          10          1.25    1
3   3        11         999999999   1.00    1

我有一个疑问

DECLARE @QuantityEntered int
DECLARE @ClassEntered int

SET @QuantityEntered = 10;
SET @ClassEntered = 1

SELECT IIf(@QuantityEntered>=TierPricing.MaxValue,TierPricing.MaxValue*TierPricing.Price,(@QuantityEntered-(TierPricing.MinValue-1))*TierPricing.Price)) AS RangePrice
FROM 
  TierPricing
WHERE 
  (((TierPricing.MinValue)<=@QuantityEntered) AND ((TierPricing.Class)=@ClassEntered));

---

我的查询出了什么问题？

当我发现你的问题时，我正试图自己解决这个问题。我想出了一种基于集合的方法来获得正确的结果，但是您必须将最小值和最大值更改为从0开始，从较低层的末端开始。因此，层现在是0-5、5-10和10-9999999。以下是对您的问题的重新解释：

create table #TierPricing
(
     CID int
    ,RangeId int
    ,MinValue int
    ,MaxValue int
    ,Price money
    ,Class int
)

insert into #TierPricing(CID, RangeId, MinValue, MaxValue, Price, Class) values (1,1,0,5,1.50,1)
insert into #TierPricing(CID, RangeId, MinValue, MaxValue, Price, Class) values (2,2,5,10,1.25,1)
insert into #TierPricing(CID, RangeId, MinValue, MaxValue, Price, Class) values (3,3,10,999999999,1.00,1)

DECLARE @QuantityEntered int
DECLARE @ClassEntered int

SET @QuantityEntered = 10;
SET @ClassEntered = 1

;with t as (
select
    #TierPricing.*
    ,case
        when @QuantityEntered > MaxValue then MaxValue - MinValue --The @QuantityEntered fills up the entire tier
        when @QuantityEntered > MinValue then @QuantityEntered - MinValue --The @QuantityEntered partillay fills the tier
        else 0
        end as TierQuantity 
from #TierPricing   
)
select
    sum(TierQuantity * Price) as RangePrice
from t

drop table #TierPricing

---

当

@QuantityEntered

设置为10时，将返回13.75。

为什么“@QuantityEntered=10应返回13.75”，而不仅仅是12.50（1.25 x 10）？@Anton。因为第1到第5项的费用为1.50，第6到第10项的费用为1.25。您能在TierPricing中再添加一列，比如TotalPriceAdjustment吗？例如，从6到10的所有项目都有7.50，从11到999999的所有项目都有13.75。然后查询将很简单，公式是：TotalPriceAdjustment+（Value-MinValue+1）x PriceUh。。。你所需要做的就是将

IIf（@QuantityEntered>=

更改为

IIf（@QuantityEntered>

），其实没关系。这就解决了10个问题。实际的解决方法就是将

TierPricing.MaxValue*TierPricing.Price

更改为

（TierPricing.MaxValue-TierPricing.MinValue+1）*TierPricing.Price

create table #TierPricing
(
     CID int
    ,RangeId int
    ,MinValue int
    ,MaxValue int
    ,Price money
    ,Class int
)

insert into #TierPricing(CID, RangeId, MinValue, MaxValue, Price, Class) values (1,1,0,5,1.50,1)
insert into #TierPricing(CID, RangeId, MinValue, MaxValue, Price, Class) values (2,2,5,10,1.25,1)
insert into #TierPricing(CID, RangeId, MinValue, MaxValue, Price, Class) values (3,3,10,999999999,1.00,1)

DECLARE @QuantityEntered int
DECLARE @ClassEntered int

SET @QuantityEntered = 10;
SET @ClassEntered = 1

;with t as (
select
    #TierPricing.*
    ,case
        when @QuantityEntered > MaxValue then MaxValue - MinValue --The @QuantityEntered fills up the entire tier
        when @QuantityEntered > MinValue then @QuantityEntered - MinValue --The @QuantityEntered partillay fills the tier
        else 0
        end as TierQuantity 
from #TierPricing   
)
select
    sum(TierQuantity * Price) as RangePrice
from t

drop table #TierPricing