Oracle删除重复记录妙解

上一篇 / 下一篇 2017-08-17 20:15:53 / 个人分类：数据库知识

少量数据：

三部曲：

1.create table a as select distinct * from b;

2.truncate table b;

3.insert into b select * from a;

大量数据：

way1: delete from test a where rowid not in(select max(b.rowid) from test b where a.id=b.id and a.name=b.name...)

way2: delete from test a where rowid <(select max(b.rowid) from test b where a.id=b.id.....)(换>,则 max换min)

way3: delete from test where rowid not in (select max(rowid) from test a group by a.id,a.name...)