按条件限量随机提取记录问题
DECLARE   @test1   table(c1   varchar(10),c2   varchar(10))
INSERT   INTO   @test1   (c1,c2)
                    SELECT   '1 ', 'a '
UNION   ALL   SELECT   '2 ', 'a '
UNION   ALL   SELECT   '3 ', 'a '
UNION   ALL   SELECT   '4 ', 'b '
UNION   ALL   SELECT   '5 ', 'b '
UNION   ALL   SELECT   '6 ', 'b '
UNION   ALL   SELECT   '7 ', 'b '
UNION   ALL   SELECT   '8 ', 'c '
UNION   ALL   SELECT   '9 ', 'c '
UNION   ALL   SELECT   '10 ', 'd '
UNION   ALL   SELECT   '11 ', 'd '
UNION   ALL   SELECT   '12 ', 'd '
UNION   ALL   SELECT   '13 ', 'e '
UNION   ALL   SELECT   '14 ', 'e '
UNION   ALL   SELECT   '15 ', 'e '

DECLARE   @test2   table   (c2   varchar(10),cnt   int)
INSERT   INTO   @test2   (c2,MaxCnt)
                    SELECT   'a ',2
UNION   ALL   SELECT   'c ',1
UNION   ALL   SELECT   'd ',1

问题是在@test1中随机提取N条记录，记录不重复。
所取记录的c2次数不大于@test2中c2所对应的MaxCnt。
@test2中没对应的c2表示没有数量限制。
请问有没有方法能用一条语句高效实现？

------解决方案--------------------
取n条随机记录
select top n from @test1 order by newid()
------解决方案--------------------
比如楼主的数据，N=10

create table #(id varchar(5))
insert into # select 3
union all select 3
union all select 8
union all select 8

drop table #count
create table #count(ctid varchar(5))
insert into #count select '+ '
union all select '- '
union all select '* '
union all select '/ '

select identity(int,1,1) id, '( '+aid+b.ctid+ '( '+bid+c.ctid+ '( '+cid+d.ctid+did+ '))) '[mula] into #wei
from
(select DISTINCT a.id [aid],b.id [bid],c.id [cid],d.id+ '.0 ' [did] from # a,# b,# c,# d
where len(REPLACE(a.id+b.id+c.id+d.id, '3 ', ' '))=3
and len(REPLACE(a.id+b.id+c.id+d.id, '8 ', ' '))=3
and len(REPLACE(a.id+b.id+c.id+d.id, '8 ', ' '))=2)a
,#count b,#count c,#count d

create table #show(id int identity(1,1),result dec(18,3))

declare @int int,@var varchar(50)
set @int=1
while @int <=(select max(id)from #wei)
begin
select @var=mula from #wei where id=@int
insert into #show exec( 'select '+@var)
if(@@ERROR=8134)
insert into #show select null
set @int=@int+1
end

select * from #wei a join #show b on b.id=a.id
where b.result=24

drop table #count
drop table #
drop table #wei
drop table #show


DECLARE @test1 table(c1 varchar(10),c2 varchar(10))
INSERT INTO @test1 (c1,c2)
SELECT '1 ', 'a '
UNION ALL SELECT '2 ', 'a '
UNION ALL SELECT '3 ', 'a '
UNION ALL SELECT '4 ', 'b '
UNION ALL SELECT '5 ', 'b '
UNION ALL SELECT '6 ', 'b '