create table test(keyId int identity,info varchar(10),flag int)
go
 
insert into test(info,flag)values ('a',-100),('b',-2),('C',-3)
,('d',2),('e',4),('f',8),('g',9),('h',0),('e',1),('f',0)
go
 
---将flag值等于0的放入最前面显示
select * from test order by 
case when flag =0 then 0 else 1 end ,
flag asc 
go
 
---将flag值等于2的放入最前面显示
select * from test order by 
case when flag =2 then 0 else 1 end ,
flag asc 
go
 
go
truncate table test
drop table test