Oracle里删除重复记录，保留一项

我们在使用数据库的时候，有时数据会有所重复，当我们只需要一项数据时，不需要显示重复的记录时

如下就有SQL代码：

--查找表中多余的重复记录，重复记录是根据单个字段来判断
select * from people where peopleId in(select peopleId from people group by peopleId
having count(peopleId)>1);

--删除表中多余的重复记录，重复记录是根据单个字段来判断，只保留rowid最小的记录
delete from people where peoplename in(select peoplename from people group by peoplename  having count(peoplename)>1)
and peopleId not in (select min(peopleId) from people group by peoplename  having count(peoplename)>1);

--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);

--删除表中多余的重复记录（多个字段），只保留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);