查询并删除重复记录的SQL语句

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)