SQL Server首先获得排名？

Question

编辑 - 重申我的需要，因为两个家伙的方式比我更容易误解我的问题，所以我需要使这个更好...

我有一个像下面的表。我需要选择“ison”列为1的第一组'sec1'行的所有行。因此，查询应该首先返回'bbb'行，但是如果我将所有行设置为ison = 0，然后使'ccc'行ison = 1，那么我会在结果集中得到两行'ccc'。任何人都可以帮助我与我的排名/顶部？使用MSSQL 2008.

create table #grp (sec1 varchar(4) , sec2 varchar(4) , ison bit) 
insert into #grp values ('aaa' , '001' , 0) 
insert into #grp values ('aaa' , '002' , 0) 
insert into #grp values ('bbb' , '001' , 1) 
insert into #grp values ('ccc' , '001' , 1) 
insert into #grp values ('ccc' , '001' , 1) 

Select * From 
(Select 
    sec1 , 
    sec2 , 
    ison , 
    RANK() Over (partition by sec1 order by sec1,sec2) as rowrank 
from #grp 
where ison=1 
) tmp 
where rowrank=1 

谢谢。

Answer 1

create table #grp (sec1 varchar(4) , sec2 varchar(4) , ison bit) 
insert into #grp values ('aaa' , '001' , 0) 
insert into #grp values ('aaa' , '002' , 1) 
insert into #grp values ('bbb' , '001' , 1) 
insert into #grp values ('ccc' , '001' , 1) 
insert into #grp values ('ccc' , '001' , 1) 

SELECT * 
    FROM #grp 
WHERE sec1 = (
        Select TOP(1) sec1 
        From 
         (Select 
           sec1 , 
           sec2 , 
           ison , 
           RANK() Over (partition by sec1 order by sec1,sec2) as rowrank 
          from #grp 
          where ison=1 
         ) tmp 
        where rowrank=1 
        Order by sec1, Sec2 
       )