询问一个SQL写法

[zhuhua]

一个表的字段
D A B C
1 1 2 3
2 1 2 4
3 2 3 4
4 2 3 5
要求的效果
D A B C
1 1 2 3
3 2 3 4

其中D是主键，要求取A字段相同情况下的第一条

[xeqtr1982]

declare @t table(D int,A int,B int,C int)
insert into @t select 1,1,2,3
union all select 2,1,2,4
union all select 3,2,3,4
union all select 4,2,3,5

select * from @t a where exists(select 1 from @t where A=a.A and D>a.D)

--这样吗？

[撸大湿]

create table #tb(D int,A int,B int,C int)
insert into #tb
select 1,1,2,3 union all
select 2,1,2,4 union all
select 3,2,3,4 union all
select 4,2,3,5

select * from #tb a where
exists(select 1 from #tb where A=a.A and D>a.D)
drop table #tb

[paoluo]

Select * from TableName A Where D In (Select TOP 1 D from TableName Where A=A.A Order By D)