Oracle去除数据的常用方法

1. dinstinct
2. row_number()

   select *
     from (select t1.*,
                  row_number() over(partition by t1.col_2, t1.col_3 order by 1) rn
             from nayi224_180824 t1) t1
    where t1.rn = 1
   ;

 针对指定列，查出所有重复行

select *
  from (select t1.*,
               count(1) over(partition by t1.col_2, t1.col_3) rn
          from nayi224_180824 t1) t1
 where t1.rn > 1
;