请问关于删除数据库里主键不同，其他字段相同的SQL语句

请教关于删除数据库里主键不同，其他字段相同的SQL语句！
数据库里有一个表document，
这个表有三个字段ID(主键),DocumentID,DocumentName
假如这个表里有三条数据
第一条8941ada0-bc47-4ee3-9bae-5dd660bc75e5，1，doc1
第二条bc53ec55-f776-4f88-91e5-827e1d9595a8，1，doc1
第三条547d2b1a-3233-41dd-8578-d3a25f3ef911，1，doc1

那么我怎么写SQL语句，删除其中的两条，只留下一条。
数据库里这样的数据很多，几百行吧。
求救！！！请大家帮忙！！！先谢谢了

[解决办法]

SQL code

delete t from tb t where exists(select 1 from  tb where DocumentID=DocumentID and DocumentName=t.DocumentName and id<t.id)
[解决办法]
SQL code
delete from  document where not exsits (select max(id),DocumentID,DocumentNamefrom document )
[解决办法]
SQL code
with cte as(select *,row_number()over(partition by DocumentID,DocumentName order by getdate())as RN from tb)delete from cte where RN>1
[解决办法]
SQL code
------------------------------ Author  :fredrickhu(小F，向高手学习)-- Date    :2011-11-03 16:15:46-- Version:--      Microsoft SQL Server 2008 R2 (RTM) - 10.50.1617.0 (Intel X86) --    Apr 22 2011 11:57:00 --    Copyright (c) Microsoft Corporation--    Enterprise Evaluation Edition on Windows NT 6.1 <X64> (Build 7600: ) (WOW64)--------------------------------> 测试数据：[tb]if object_id('[tb]') is not null drop table [tb]go create table [tb]([ID] uniqueidentifier,[DocumentID] int,[DocumentName] varchar(4))insert [tb]select '8941ada0-bc47-4ee3-9bae-5dd660bc75e5',1,'doc1' union allselect 'bc53ec55-f776-4f88-91e5-827e1d9595a8',1,'doc1' union allselect '547d2b1a-3233-41dd-8578-d3a25f3ef911',1,'doc1'--------------开始查询--------------------------delete t from tb t where exists(select 1 from  tb where DocumentID=DocumentID and DocumentName=t.DocumentName and id<t.id)select * from tb ----------------结果----------------------------/* ID                                   DocumentID  DocumentName------------------------------------ ----------- ------------8941ADA0-BC47-4EE3-9BAE-5DD660BC75E5 1           doc1(1 行受影响)*/
[解决办法]
SQL code
create table document(ID varchar(50),DocumentID int,DocumentName varchar(10))insert into document select '8941ada0-bc47-4ee3-9bae-5dd660bc75e5',1,'doc1'insert into document select 'bc53ec55-f776-4f88-91e5-827e1d9595a8',1,'doc1'insert into document select '547d2b1a-3233-41dd-8578-d3a25f3ef911',1,'doc1'godelete t from document t where exists(select 1 from document where DocumentID=t.DocumentID and DocumentName=t.DocumentName and ID>t.id)select * from document /*ID                                                 DocumentID  DocumentName-------------------------------------------------- ----------- ------------bc53ec55-f776-4f88-91e5-827e1d9595a8               1           doc1(1 行受影响)*/godrop table document
[解决办法]
SQL code
delete from  document where not exsits (select max(id),DocumentID,DocumentNamefrom document  where  DocumentID=DocumentID and DocumentName=DocumentName )