求一 sql语句?
表a  
bid   column1   column   2
1         aaa           bbb
2         ccc           ddd
表b
id     bid     column3   column4
1       1           eeeee       ffff
2       1           ggggg       hhh
3       2           uuuu           iii
我要显示的效果
bid   column1   column2   column3   column4
1         aaa           bbb             eeeee   ffff
2         ccc           ddd             uuuu     iii
也就是不要显示表b中有重复的bid

------解决方案--------------------

select a.*,b.column3, b.column4 from
a inner join (
select * from b a where not exists( select 1 from b where a.bid=bid and a.id> id))b
on a.bid=b.bid
------解决方案--------------------
declare @ta table(bid int, column1 varchar(10), column2 varchar(10))
insert @ta
select 1, 'aaa ', 'bbb ' union all
select 2, 'ccc ', 'ddd '
declare @tb table(id int, bid int,column3 varchar(10), column4 varchar(10))
insert @tb
select 1, 1, 'eeeee ', 'ffff ' union all
select 2, 1, 'ggggg ', 'hhh ' union all
select 3, 2, 'uuuu ', 'iii '

select a.*,b.column3,b.column4 from @ta as a
left join
(select * from @tb as t where not exists(select 1 from @tb where bid = t.bid and id < t.id)) as b
on a.bid = b.bid

/*结果
bid column1 column2 column3 column4
--------------------------------------
1 aaa bbb eeeee ffff
2 ccc ddd uuuu iii
*/