Oracle查询并删除重复记录的SQL语句
2010-07-20 00:00出处：中国IT实验室作者：佚名【我要评论】 [导读]查找表中多余的重复记录，重复记录是根据单个字段(peopleId)来判断。
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查询及删除重复记录的SQL语句
1、查找表中多余的重复记录，重复记录是根据单个字段(peopleId)来判断
select * from people
where peopleId in (select peopleId from people group by peopleId having count(peopleId) >1)
2、删除表中多余的重复记录，重复记录是根据单个字段(peopleId)来判断，只留有 rowid最小的记录
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)
注:rowid为oracle自带不用该.....
3、查找表中多余的重复记录(多个字段)
select * from vitae a
where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) >1)
4、删除表中多余的重复记录(多个字段)，只留有rowid最小的记录
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、查找表中多余的重复记录(多个字段)，不包含rowid最小的记录
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)
(二)
比方说
在A表中存在一个字段“name”，
而且不同记录之间的“name”值有可能会相同，
现在就是需要查询出在该表中的各记录之间，“name”值存在重复的项;
Select Name,Count(*) From A Group By Name Having Count(*) >1
如果还查性别也相同大则如下:
Select Name,sex,Count(*) From A Group By Name,sex Having Count(*) >1
(三)
方法一
declare @max integer,@id integer
declare cur_rows cursor local for select 主字段,count(*) from 表名 group by 主字段 having count(*) >; 1
open cur_rows
fetch cur_rows into @id,@max
while @@fetch_status=0
begin
select @max = @max -1
set rowcount @max
delete from 表名 where 主字段 = @id
fetch cur_rows into @id,@max
end
close cur_rows
set rowcount 0 方法二
"重复记录"有两个意义上的重复记录，一是完全重复的记录，也即所