求大神，递归求和

[jasontimmy]

if not object_id(N'#A') is null
drop table #A
if not object_id(N'#B') is null
drop table #B
Go

create Table #A(
id int,
qty int)
insert into #A
select 1,1 union all
select 1,1 union all
select 2,1 union all
select 2,1 union all
select 3,1 union all
select 4,1
go

create table #B(
id int,
subid int)
insert into #B
select 2,3 union all
select 2,4

输出#A表求和结果不含子id
id qty
1 2
2 4

[顺势而为1]

Select a.id,sum(a.qty) as qty
From #A a
    Left Join #B b on a.id=b.id
Where a.id not in (Select subid From #B)
Group By a.id

[唐诗三百首]

select id=isnull(b.id,a.id),
       qty=sum(a.qty)
 from #A a
 left join #B b on a.id=b.subid
 group by isnull(b.id,a.id)

/*
id          qty
----------- -----------
1           2
2           4

(2 rows affected)
*/