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  /**//**
 **刪除表中的重復(fù)記錄
**@author zdw
** 2008 11.03 17:30
 **/
--創(chuàng)建測試表
if object_id('test') is not null
drop table test
create table test
(
id int identity(1,1) primary key,
name varchar(50)
)
--插入幾條測試數(shù)據(jù)
insert into test select 'a' union all
select 'a' union all
select 'a' union all
select 'a' union all
select 'a' union all
select 'a' union all
select 'b' union all
select 'b' union all
select 'b' union all
select 'b' union all
select 'b' union all
select 'b' union all
select 'b' union all
select 'c' union all
select 'c' union all
select 'c' union all
select 'd' union all
select 'd'
--查看當(dāng)前記錄
select * from test
if object_id('#') is not null
drop table #
--注意(是單個(gè)字段的不同還是多個(gè)字段,這里是name)
select distinct (name) into # from test
--查看新表中的數(shù)據(jù)
select * from #
--清空舊表
truncate table test
--將新表中的數(shù)據(jù)插入到舊表
insert test select * from #
--刪除新表
drop table #
--查看結(jié)果
select * from test
csdn上秒到的一些方法：
1、查找表中多余的重復(fù)記錄，重復(fù)記錄是根據(jù)單個(gè)字段（peopleId）來判斷
select * from people
where peopleId in (select peopleId from people group by peopleId having count(peopleId) > 1)
2、刪除表中多余的重復(fù)記錄，重復(fù)記錄是根據(jù)單個(gè)字段（peopleId）來判斷，只留有rowid最小的記錄
delete from people
where peopleId in (select peopleId from people group by peopleId having count(peopleId) > 1)
and rowid not in (select min(rowid) from people group by peopleId having count(peopleId )>1)
3、查找表中多余的重復(fù)記錄（多個(gè)字段）
select * from vitae a
where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)
4、刪除表中多余的重復(fù)記錄（多個(gè)字段），只留有rowid最小的記錄
delete from vitae a
where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)
and rowid not in (select min(rowid) from vitae group by peopleId,seq having count(*)>1)
5、查找表中多余的重復(fù)記錄（多個(gè)字段），不包含rowid最小的記錄
select * from vitae a
where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)
and rowid not in (select min(rowid) from vitae group by peopleId,seq having count(*)>1)
比方說在A表中存在一個(gè)字段“name”，而且不同記錄之間的“name”值有可能會(huì)相同，
現(xiàn)在就是需要查詢出在該表中的各記錄之間，“name”值存在重復(fù)的項(xiàng)；
Select Name,Count(*) From A Group By Name Having Count(*) > 1
如果還查性別也相同大則如下:
Select Name,sex,Count(*) From A Group By Name,sex Having Count(*) > 1
還有什么好的解決方法，請大家一起分享。
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