使用 FIFO 方法计算 SQL 的销售成本

Question

根据股票交易 table 我创建了以下排序视图 table 为 FIFO 做好准备：

rowN	date_	stockCode	sign_	amount	unitPrice
1	'2022-01-20'	ABC	in	5	29.20
2	'2022-01-22'	ABC	in	3	32.50
3	'2022-01-23'	ABC	out	7	40.00
4	'2022-01-23'	ABC	out	1	42.00
5	'2022-01-01'	XYZ	in	3	20.50
6	'2022-01-03'	XYZ	out	3	25.00

我想创建一个 select 查询，它看起来像之前的 table，只有“out”行并添加了 cost_of_sales 列，这是该销售的 FIFO 成本。但是我对 SQL 的了解仅限于对分区的连接和求和。

结果table在我看来应该是这样的：

rowN	date_	stockCode	sign_	amount	unitPrice	cost_of_sales_uP	cost_of_sales
3	'2022-01-23'	ABC	out	7	40.00	30.1428	211.00
4	'2022-01-23'	ABC	out	1	42.00	32.50	32.50
6	'2022-01-03'	XYZ	out	3	25.00	20.50	61.50

我不知道如何实现。任何帮助和指导表示赞赏。结果 table 不必完全一样，但主要思想就在那里。

谢谢！

Answer 1

以下方法可能不是最快的。
但它完成了工作。

首先将传入的内容展开为临时 table。

然后，通过循环传出，每个传入单元在 First-In-First-Out 的基础上分配给传出。

最后的查询然后使用 temp table 的结果来计算传入的总数和平均值。

IF OBJECT_ID('tempdb..#tmpStock') IS NOT NULL DROP TABLE #tmpStock;
CREATE TABLE #tmpStock (
  id int identity primary key,
  code varchar(30),
  date_in date,
  rowN int,
  unitPrice decimal(10,2),
  rowN_out int
);

--
-- Using a recursive CTE to unfold the incoming for the temp table
--
with RCTE as (
 select stockCode, date_, rowN, amount, unitPrice
 , 1 as lvl
 from stock_transactions
 where sign_ = 'in'
 
 union all
 
 select stockCode, date_, rowN, amount, unitPrice
 , lvl + 1
 from RCTE
 where lvl < amount
)
insert into #tmpStock (code, date_in, rowN, unitPrice)
select stockCode, date_, rowN, unitPrice
from RCTE
order by stockCode, date_, rowN
option (maxrecursion 0);

DECLARE @IdOut INT = 1;
DECLARE @RowsOut INT = 0;
DECLARE @code VARCHAR(30);
DECLARE @amount SMALLINT;
DECLARE @date DATE;
DECLARE @rowN INT;

DECLARE @StockOut TABLE (
  id int identity primary key, 
  code varchar(30),
  date_out date, 
  rowN int,
  amount smallint
);

insert into @StockOut (code, date_out, rowN, amount)
select stockCode, date_, rowN, amount
from stock_transactions
where sign_ = 'out'
order by stockCode, date_, rowN;

SELECT @RowsOut = COUNT(*) FROM @StockOut;
 
WHILE @IdOut <= @RowsOut
BEGIN
   SELECT 
     @code = code
   , @amount = amount
   , @date = date_out
   , @rowN = rowN
   FROM @StockOut
   WHERE id = @IdOut;

   ;WITH cte_in as (
     select *
     , rn = row_number() over (order by date_in, rowN)
     from #tmpStock 
     where code = @code 
       and date_in <= @date
       and rowN_out is null
   ) 
   UPDATE cte_in 
   SET rowN_out = @rowN
   WHERE rn <= @amount;

   SET @IdOut = @IdOut + 1;
END;

select * from #tmpStock

id | code | date_in    | rowN | unitPrice | rowN_out
-: | :--- | :--------- | ---: | --------: | -------:
 1 | ABC  | 2022-01-20 |    1 |     29.20 |        3
 2 | ABC  | 2022-01-20 |    1 |     29.20 |        3
 3 | ABC  | 2022-01-20 |    1 |     29.20 |        3
 4 | ABC  | 2022-01-20 |    1 |     29.20 |        3
 5 | ABC  | 2022-01-20 |    1 |     29.20 |        3
 6 | ABC  | 2022-01-22 |    2 |     32.50 |        3
 7 | ABC  | 2022-01-22 |    2 |     32.50 |        3
 8 | ABC  | 2022-01-22 |    2 |     32.50 |        4
 9 | XYZ  | 2022-01-01 |    5 |     20.50 |        6
10 | XYZ  | 2022-01-01 |    5 |     20.50 |        6
11 | XYZ  | 2022-01-01 |    5 |     20.50 |        6

SELECT o.*
, CAST(i.AveragePriceIn AS DECIMAL(10,2)) AS cost_of_sales_uP
, i.TotalPriceIn AS cost_of_sales
FROM stock_transactions o
LEFT JOIN (
  SELECT rowN_out
  , AVG(unitPrice) as AveragePriceIn
  , SUM(unitPrice) as TotalPriceIn
  FROM #tmpStock
  GROUP BY rowN_out
) i on i.rowN_out = o.rowN
WHERE o.sign_ = 'out'
ORDER BY o.rowN;

rowN | date_      | stockCode | sign_ | amount | unitPrice | cost_of_sales_uP | cost_of_sales
---: | :--------- | :-------- | :---- | -----: | --------: | ---------------: | ------------:
   3 | 2022-01-23 | ABC       | out   |      7 |     40.00 |            30.14 |        211.00
   4 | 2022-01-23 | ABC       | out   |      1 |     42.00 |            32.50 |         32.50
   6 | 2022-01-03 | XYZ       | out   |      3 |     25.00 |            20.50 |         61.50

演示 db<>fiddle here

使用 FIFO 方法计算 SQL 的销售成本

Calculating Cost of Sales in SQL using FIFO method

sql

sql-server

fifo