很經(jīng)典的“先進先出”的庫存處理的SQL語句。

 CREATE TABLE #tmp  (
	ID int IDENTITY (1, 1),
	單價 decimal(18, 2) NOT NULL ,
	數(shù)量 decimal(18, 2) NOT NULL ,
	已出數(shù)量 decimal(18, 2) NOT NULL
)
insert into #tmp(單價,數(shù)量,已出數(shù)量) values(1.1,50,0)
insert into #tmp(單價,數(shù)量,已出數(shù)量) values(1.3,30,0)
insert into #tmp(單價,數(shù)量,已出數(shù)量) values(1.4,60,0)
insert into #tmp(單價,數(shù)量,已出數(shù)量) values(1.5,20,0)


declare @t decimal(18, 2),@temp decimal(18, 2)
set @t=90

update #tmp set @temp=case when @t>數(shù)量 then 數(shù)量 else @t end,數(shù)量=數(shù)量-@temp,@t=@t-@temp
from #tmp 
where 單價<=1.30
select * from #tmp 
go
drop table #tmp 




CREATE TABLE #tmp  (
	ID int IDENTITY (1, 1),
	單價 decimal(18, 2) NOT NULL ,
	數(shù)量 decimal(18, 2) NOT NULL ,
	已出數(shù)量 decimal(18, 2) NOT NULL
)
insert into #tmp(單價,數(shù)量,已出數(shù)量) values(1.1,50,0)
insert into #tmp(單價,數(shù)量,已出數(shù)量) values(1.3,30,0)
insert into #tmp(單價,數(shù)量,已出數(shù)量) values(1.4,60,0)
insert into #tmp(單價,數(shù)量,已出數(shù)量) values(1.5,20,0)


declare @t decimal(18, 2),@temp decimal(18, 2),@a varchar(8000)
select @t=60,@a=''

update #tmp set @temp=case when @t>數(shù)量-已出數(shù)量 then 數(shù)量-已出數(shù)量 else @t end, @t=@t-@temp,@a=@a+','+cast(@temp as varchar(10)),已出數(shù)量=@temp+已出數(shù)量 where 已出數(shù)量<>數(shù)量
select * from #tmp

set @t=30

update #tmp set @temp=case when @t>數(shù)量-已出數(shù)量 then 數(shù)量-已出數(shù)量 else @t end,@t=@t-@temp,@a=@a+','+cast(@temp as varchar(10)),已出數(shù)量=@temp+已出數(shù)量 where 已出數(shù)量<>數(shù)量
select * from #tmp

select right(@a,len(@a)-1)
go
drop table #tmp


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