求一句SQL ，分组后排序。

[shuifengcun]

比如有这些一些数据
c0,c1,c2
-------------
a,2,2003
b,3,2003
c,4,2003
a,1,2004
b,1,2004
c,2,2004

我要取每一年的排名前2位的，谢谢

[子陌红尘]

select t.* from 表 t where c0 in(select top 2 c0 from 表 where c2=t.c2 order by c1)

[--小F--]

---------------------------------
--  Author: liangCK 小梁
--  Title : 查每个分组前N条记录
--  Date  : 2008-11-13 17:19:23
---------------------------------

--> 生成测试数据: #T
IF OBJECT_ID('tempdb.dbo.#T') IS NOT NULL DROP TABLE #T
CREATE TABLE #T (ID VARCHAR(3),GID INT,Author VARCHAR(29),Title VARCHAR(39),Date DATETIME)
INSERT INTO #T
SELECT '001',1,'邹建','深入浅出SQLServer2005开发管理与应用实例','2008-05-10' UNION ALL
SELECT '002',1,'胡百敬','SQLServer2005性能调校','2008-03-22' UNION ALL
SELECT '003',1,'格罗夫Groff.J.R.','SQL完全手册','2009-07-01' UNION ALL
SELECT '004',1,'KalenDelaney','SQLServer2005技术内幕存储引擎','2008-08-01' UNION ALL
SELECT '005',2,'Alex.Kriegel.Boris.M.Trukhnov','SQL宝典','2007-10-05' UNION ALL
SELECT '006',2,'飞思科技产品研发中心','SQLServer2000高级管理与开发','2007-09-10' UNION ALL
SELECT '007',2,'胡百敬','SQLServer2005数据库开发详解','2008-06-15' UNION ALL
SELECT '008',3,'陈浩奎','SQLServer2000存储过程与XML编程','2005-09-01' UNION ALL
SELECT '009',3,'赵松涛','SQLServer2005系统管理实录','2008-10-01' UNION ALL
SELECT '010',3,'黄占涛','SQL技术手册','2006-01-01'

--SQL查询如下:

--按GID分组,查每个分组中Date最新的前2条记录


--1.字段ID唯一时:
SELECT * FROM #T AS T WHERE ID IN(SELECT TOP 2 ID FROM #T WHERE GID=T.GID ORDER BY Date DESC)

--2.如果ID不唯一时:
SELECT * FROM #T AS T WHERE 2>(SELECT COUNT(*) FROM #T WHERE GID=T.GID AND Date>T.Date)

--SQL Server 2005 使用新方法

--3.使用ROW_NUMBER()进行排位分组
SELECT ID,GID,Author,Title,Date
FROM
(
   SELECT rid=ROW_NUMBER() OVER(PARTITION BY GID ORDER BY Date DESC),*
   FROM #T
) AS T
WHERE rid<=2

--4.使用APPLY
SELECT DISTINCT b.*
FROM #T AS a
CROSS APPLY
(
    SELECT TOP(2) * FROM #T WHERE a.GID=GID ORDER BY Date DESC
) AS b


--结果
/*

ID   GID         Author                        Title                                   Date
---- ----------- ----------------------------- --------------------------------------- -----------------------
003  1           格罗夫Groff.J.R.                 SQL完全手册                                 2009-07-01 00:00:00.000
004  1           KalenDelaney                  SQLServer2005技术内幕存储引擎                   2008-08-01 00:00:00.000
005  2           Alex.Kriegel.Boris.M.Trukhnov SQL宝典                                   2007-10-05 00:00:00.000
007  2           胡百敬                           SQLServer2005数据库开发详解                    2008-06-15 00:00:00.000
009  3           赵松涛                           SQLServer2005系统管理实录                     2008-10-01 00:00:00.000
010  3           黄占涛                           SQL技术手册                                 2006-01-01 00:00:00.000

(6 行受影响)
*/

[jiangshun]

排名前二位？C1吗？是按升序还是降序？

[jwdream2008]

向楼上学习！

[华夏小卒]

...

[feixianxxx]

select t.* from 表 t 
where c0 in(select top 2 with ties c0 from 表 where c2=t.c2 order by c1)

[dawugui]

select t.* from tb t where c1 in (select top 2 c1 from tb where c2 = t.c2 order by c1 desc) order by t.c2 , t.c1 desc

[--小F--]

SELECT * FROM tb AS T WHERE 2>(SELECT COUNT(*) FROM tb WHERE c2=T.c2 AND c1>T.c1)

[--小F--]

[Quote=引用 7 楼 dawugui 的回复:]
SQL codeselect t.*from tb twhere c1in (selecttop2 c1from tbwhere c2= t.c2orderby c1desc)orderby t.c2 , t.c1desc
[/Quote]


乌龟终于回来了

[快乐_石头]

--> Title  : Generating test data [tb]
--> Author : wufeng4552
--> Date   : 2009-11-06 16:39:04
if object_id('[tb]') is not null drop table [tb]
go
create table [tb] (c0 nvarchar(2),c1 int,c2 int)
insert into [tb]
select 'a',2,2003 union all
select 'b',3,2003 union all
select 'c',4,2003 union all
select 'a',1,2004 union all
select 'b',1,2004 union all
select 'c',2,2004
;with stone
as
(select *,cnt=row_number()over(partition by c2 order by c1 desc)from tb)
select * from stone where cnt<=2
/*
c0   c1          c2          cnt
---- ----------- ----------- --------------------
c    4           2003        1
b    3           2003        2
c    2           2004        1
a    1           2004        2
*/

[阿_布]

学习！

[feixianxxx]

select t.* 
from (select *, DENSE_RANK() OVER(partition by c2 ORDER BY c1 ) AS denserank from 表 t) t  
where denserank=1 or denserank =2

[dawugui]

create table tb(c0 varchar(10),c1 int,c2 int)
insert into tb values('a',2,2003) 
insert into tb values('b',3,2003) 
insert into tb values('c',4,2003) 
insert into tb values('a',1,2004) 
insert into tb values('b',1,2004) 
insert into tb values('c',2,2004)
go

select t.* from tb t where c1 in (select top 2 c1 from tb where c2 = t.c2 order by c1 desc) order by t.c2 , t.c1 desc
/*
c0         c1          c2          
---------- ----------- ----------- 
c          4           2003
b          3           2003
c          2           2004
a          1           2004
b          1           2004

（所影响的行数为 5 行）
*/

select m.c0 , m.c1 , m.c2 from
(
  select t.* , px = (select count(1) from tb where c2 = t.c2 and (c1 > t.c1 or (c1 = t.c1 and c0 > t.c0) )) + 1 from tb t
) m
where px <= 2 
order by m.c2 , m.c1 desc
/*
c0         c1          c2          
---------- ----------- ----------- 
c          4           2003
b          3           2003
c          2           2004
b          1           2004

（所影响的行数为 4 行）
*/

drop table tb 

[ming1921]

看来还应该好好学习啊

[dawugui]

[Quote=引用 9 楼 fredrickhu 的回复:]
引用 7 楼 dawugui 的回复:
SQL codeselect t.*from tb twhere c1in (selecttop2 c1from tbwhere c2= t.c2orderby c1desc)orderby t.c2 , t.c1desc



乌龟终于回来了
[/Quote]还没有,正在机场侯机.