oracle은 써본적이 없어서..

mssql 로 작성되었습니다.

--쿼리 시작

with table_a as
(
    select 1  As data
)
,table_b as
(
      Select
             a.data
            ,0   As seq
        From table_a a
   
   Union All
    
      Select
             a.data
            ,seq = a.seq + 1
        From table_b a
       Where seq < 100
)
,table_c as
(     
      Select
             a.data
            ,seq = a.seq + 1
            ,num = Convert(Decimal(18,0),Round(( a.seq / 50 ) + 0.5 ,0))
        From table_b a
)
  Select
         a.data
        ,a.seq
        ,a.num
    From table_c a
   

--결과

seq 1 ~ 50 -> num = 1

seq 51 ~ 100 -> num = 2

seq 101  -> num = 3