求SQL，分类查询语句，写法！该怎么处理

求SQL，分类查询语句，写法！
表：
ID，类型，时间，其它

1 A 2012-04-23 18:00:00
2 A 2012-04-24 18:00:00 
3 A 2012-04-25 18:00:00
5 B 2012-04-23 18:00:00
6 B 2012-04-24 18:00:00 
7 C 2012-04-25 18:00:00
8 C 2012-04-23 18:00:00


我要按分类查询，得到 A,B,C中，时间最大的记录各1条。

我要的结果：

3 A 2012-04-25 18:00:00
6 B 2012-04-24 18:00:00
7 C 2012-04-25 18:00:00

这语法这么写？

[解决办法]

SQL code

select 类型,       时间from 表 twhere id in(select top 1 id from 表 where 类型=t.类型 order by 时间 desc)
[解决办法]
SQL code
if object_id('[TB]') is not null drop table [TB]gocreate table [TB] (ID int,类型 nvarchar(2),时间 datetime,其它 sql_variant)insert into [TB]select 1,'A','2012-04-23 18:00:00',null union allselect 2,'A','2012-04-24 18:00:00',null union allselect 3,'A','2012-04-25 18:00:00',null union allselect 5,'B','2012-04-23 18:00:00',null union allselect 6,'B','2012-04-24 18:00:00',null union allselect 7,'C','2012-04-25 18:00:00',null union allselect 8,'C','2012-04-23 18:00:00',nullselect * from [TB]select distinct B.ID,B.类型,B.时间from TB Across apply(select top 1 ID,类型,时间 from TB where 类型 = A.类型 order by 时间 desc) B/*3    A    2012-04-25 18:00:00.0006    B    2012-04-24 18:00:00.0007    C    2012-04-25 18:00:00.000*/
[解决办法]
SQL code
;with TTas(select ROW_NUMBER() over(PARTITION by 类型 order by 时间 desc )as nn ,* from TB)select ID,类型,时间 from TT where nn = 1