求条sql语句

[xysoftzhk]

表结构
(
sn int,
id int,
time datetime
)
求 id=1、time最大的记录的sn

[子陌红尘]

select top 1 sn from 表 where id=1 order by time desc

[子陌红尘]

select
t.sn
from
表 t
where
t.id=1
and
not exists(select 1 from 表 where id=t.id and time>t.time)

[chuifengde]

select id,max(b) sn from [表] where id=1 group by id

[chuifengde]

:)
select * from [表] where [time]=(select max([time]) from [表] where id=1 group by id)

[hxd001_810]

select sn
from 表
where id=1 and time=(select max(time) from 表 where id=1 group by id)