orcale删除数据库中重复数据

delete from EM_EXPERT
 
　　where MPHONE in (select MPHONE from EM_EXPERT group by MPHONE
 
　　having count(MPHONE) > 1)
 
　　and rowid not in (select min(rowid) from EM_EXPERT group by MPHONE having count(MPHONE)>1)