SQL - 從行中減去耗盡值

Question

我有一種情況，需要從一個表中獲取「消耗的數量」，並將其應用於第二個具有「批量」數量的一行或多行的表。我不知道如何更好地形容它，這是我從一個表的角度是指：

Table Pooled_Lots 
---------------------------- 
Id Pool Lot Quantity 
1 1  1 5 
2 1  2 10 
3 1  3 4 
4 2  1 7 
5 3  1 1 
6 3  2 5 

Table Pool_Consumption 
---------------------------- 
Id PoolId QuantityConsumed 
1 1  17 
2 2  8 
3 3  10 

我需要從一個SQL查詢產生的行集，將是這樣的：

Pool Lot Quantity QuantityConsumed RunningQuantity RemainingDemand SurplusOrDeficit 
1  1 5   17     0    12    NULL 
1  2 10   17     0    2    NULL 
1  3 4   17     2    0    2 
2  1 7   8     0    1    -1 
3  1 1   10     0    9    NULL 
3  2 5   10     0    4    -4 

所以， Pool_Consumption.QuantityConsumed需要在Pooled_Lots的行中減去「耗盡值」，其中Pool_Consumption.PoolId = Pooled_Lots.Pool。我想不出你會怎麼說出一個查詢，說：

• 如果不是在最後一排，AmtConsumedFromLot =數量 - QuantityConsumed如果QuantityConsumed <數量，否則數量
• 如果更多的行，QuantityConsumed = QuantityConsumed - 產品數量
• 循環直到最後一行
• 如果最後一行，AmtConsumedFromLot = QuantityConsumed

假設Id是主鍵，和所述目標DB是SQL 2 005

編輯：既然人都宣稱我是「不給足夠的信息，請關閉這個」這裏比較：有NO集很多的Pool_Consumption而來，它需要從所有大量吸取借鑑其中Pool_Consumption.PoolId = Pooled_Lots.Pool，直到QuantityConsumed要麼完全耗盡或我對減去行Pooled_Lots的最後一個子集，其中Pool_Consumption.PoolId = Pooled_Lots.Pool

我不知道該怎麼越解釋這一點。這不是一個家庭作業問題，這不是一個虛構的「思考練習」。我需要幫助，試圖找出如何正確減去QuantityConsumed對多行！

Answer 1

左作爲一個練習OP：搞清楚正確的結果給出的樣本數據，總結了以下查詢的結果：

-- Create some test data. 
declare @Pooled_Lots as table (Id int, Pool int, Lot int, Quantity int) 
insert into @Pooled_Lots (Id, Pool, Lot, Quantity) values 
    (1, 1, 1, 5), (2, 1, 2, 10), (3, 1, 3, 4), 
    (4, 2, 1, 7), 
    (5, 3, 1, 1), (6, 3, 2, 5) 
declare @Pool_Consumption as table (Id int, Pool int, QuantityConsumed int) 
insert into @Pool_Consumption (Id, Pool, QuantityConsumed) values 
    (1, 1, 17), (2, 2, 8), (3, 3, 10) 

select * from @Pooled_Lots order by Pool, Lot 
select * from @Pool_Consumption order by Pool 

; with Amos as (
    -- Start with Lot 1 for each Pool. 
    select PL.Pool, PL.Lot, PL.Quantity, PC.QuantityConsumed, 
    case 
     when PC.QuantityConsumed is NULL then PL.Quantity 
     when PL.Quantity >= PC.QuantityConsumed then PL.Quantity - PC.QuantityConsumed 
     when PL.Quantity < PC.QuantityConsumed then 0 
     end as RunningQuantity, 
    case 
     when PC.QuantityConsumed is NULL then 0 
     when PL.Quantity >= PC.QuantityConsumed then 0 
     when PL.Quantity < PC.QuantityConsumed then PC.QuantityConsumed - PL.Quantity 
     end as RemainingDemand 
    from @Pooled_Lots as PL left outer join 
     @Pool_Consumption as PC on PC.Pool = PL.Pool 
    where Lot = 1 
    union all 
    -- Add the next Lot for each Pool. 
    select PL.Pool, PL.Lot, PL.Quantity, CTE.QuantityConsumed, 
    case 
     when CTE.RunningQuantity + PL.Quantity >= CTE.RemainingDemand then CTE.RunningQuantity + PL.Quantity - CTE.RemainingDemand 
     when CTE.RunningQuantity + PL.Quantity < CTE.RemainingDemand then 0 
     end, 
    case 
     when CTE.RunningQuantity + PL.Quantity >= CTE.RemainingDemand then 0 
     when CTE.RunningQuantity + PL.Quantity < CTE.RemainingDemand then CTE.RemainingDemand - CTE.RunningQuantity - PL.Quantity 
     end 
    from Amos as CTE inner join 
     @Pooled_Lots as PL on PL.Pool = CTE.Pool and PL.Lot = CTE.Lot + 1 
) 
select *, 
    case 
    when Lot = (select max(Lot) from @Pooled_Lots where Pool = Amos.Pool) then RunningQuantity - RemainingDemand 
    else NULL end as SurplusOrDeficit 
    from Amos 
    order by Pool, Lot 

Answer 2

（基於問題的4版本，我的WiFi去了相當長的一段時間）

(SELECT 
    Pool, 
    SUM(Quantity) as Pool_Quantity 
FROM 
    Pooled_Lots 
GROUP BY 
    Pool) as Pool_Quantity_Table 

現在你有一個池數量的表格彙總到一個單一的價值。

現在完整的查詢：

SELECT 
    Pool_Consumption.PoolID as Pool, 
    Pool_Quantity_Table.Pool_Quantity as Quantity, 
    Pool_Consumption.QuantityConsumed as AmtConsumedFromLot, 
    (Pool_Quantity_Table.Pool_Quantity - Pool_Consumption.QuantityConsumed) as SurplusOrDefecit 
FROM 
    Pool_Consumption 
INNER JOIN 
    (SELECT 
    Pool, 
    SUM(Quantity) as Pool_Quantity 
    FROM 
    Pooled_Lots 
    GROUP BY 
    Pool) as Pool_Quantity_Table 
ON (Pool_Consumption.PoolID = Pool_Quantity_Table.Pool);