oracle去掉重复行
    oracle 删除重复行
有表:   
create table t_test1(   
   id        number,   
   name      varchar2(50),   
   age       number,   
   birthday  date  
);   
1、选择出重复的行   
select a.* from t_test1 a   
 where rowid <> (select max(rowid)   
                   from t_test1 b   
                  where a.id = b.id  -- where语句后面的条件是你定义重复的规则   
                    and a.name = b.name  
                    and a.age = b.age   
                    and a.birthday = b.birthday);     
2、删除重复的行   
delete from t_test1 a   
 where rowid <> (select max(rowid)   
                   from t_test1 b   
                  where a.id = b.id   
                    and a.name = b.name  
                    and a.age = b.age   
                    and a.birthday = b.birthday);