sql 2000 在没有主键以及唯一键的情况下去除重复

[lygwyc]

CREATE TABLE [dbo].[testDT](
	[bh] [varchar](50) NULL,
	[name] [varchar](50) NULL,
	[sex] [int] NULL,
	[email] [varchar](50) NULL
) 

内容

12 li 1 [e-mail]
12 li 1 [e-mail]
15 wang 0 [e-mail]
13 zhang 1 [e-mail]
13 zhang 1 [e-mail]

想要的结果
12 li 1 [e-mail]
15 wang 0 [e-mail]
13 zhang 1 [e-mail]

也就是根据编号进行过滤，如果相同编号就取任意一条数据

[开着拖拉机泡妞]

select dostinct * from tbl

[kingtiy]

select [bh],min(name) name,min(sex) sex,min(email) email  from [testDT]
group by [bh]

[dawugui]

--sql 2005
select bh , name , sex , email from
(
select t.* , row_number() over(partition by bh order by name , sex , email) px from testdt t
) m
where px = 1

[dawugui]

--sql 2005
select bh , name , sex , email from
(
  select t.* , row_number() over(partition by bh order by name , sex , email) px from testdt t
) m
where px = 1

--sql 2000，如果某个字段能根据bh区分大小，例如email
select t.* from testdt t where email = (select min(email) from testdt where bh = t.bh)
select t.* from testdt t where not exists (select 1 from testdt where bh = t.bh and email < t.email)

--如果没有任何一个（多个）字段能根据bh区分大小。则需要使用临时表
select t.* , px = identity(int,1,1) into tmp from testdt t
select t.bh , t.name , t.sex , t.email from tmp t where px = (select min(px) from tmp where bh = t.bh)
select t.bh , t.name , t.sex , t.email from tmp t where not exists (select 1 from tmp where bh = t.bh and px < t.px)

[lygwyc]

[Quote=引用 2 楼 kingtiy 的回复:]

SQL code
select [bh],min(name) name,min(sex) sex,min(email) email from [testDT]
group by [bh]
[/Quote]

还有没其他写法，数据量很大，需要的字段也多，十几万条数据，这样写效率不高啊！

[开着拖拉机泡妞]

[Quote=引用 5 楼 lygwyc 的回复:]

引用 2 楼 kingtiy 的回复:

SQL code
select [bh],min(name) name,min(sex) sex,min(email) email from [testDT]
group by [bh]


还有没其他写法，数据量很大，需要的字段也多，十几万条数据，这样写效率不高啊！
[/Quote]

这就是一个查询语句，难道还有比他效率高的？？

[lygwyc]

[Quote=引用 4 楼 dawugui 的回复:]

SQL code
--sql 2005
select bh , name , sex , email from
(
select t.* , row_number() over(partition by bh order by name , sex , email) px from testdt t
) m
where px = 1

--sql 2000，如果某个字段能根据bh区分大小，……
[/Quote]

就是没有唯一字段啊，按照你这样写的话会重复的
13 zhang 1 [e-mail]
13 zhang 1 [e-mail]

我现在是要把这个写在视图里面，视图里面不可以用临时表！

[开着拖拉机泡妞]

create view view_name as 查询语句

[dawugui]

[Quote=引用 7 楼 lygwyc 的回复:]
就是没有唯一字段啊，按照你这样写的话会重复的
13 zhang 1 [e-mail]
13 zhang 1 [e-mail]

我现在是要把这个写在视图里面，视图里面不可以用临时表！[/Quote]
最简单的方法就是楼上直接根据bh分组.
--查询
select bh , max(name) name , max(sex) sex , max(email) emial from testdt group by bh
--创建视图
create view my_view as
select bh , max(name) name , max(sex) sex , max(email) emial from testdt group by bh