oracle query: get rows number and create conditions

to create the conditions in which the same data does not need to be displayed but still display different data

example:

item code	item name	value	reward	total
001	pen	500	500	1000
001	pen	600	500	1100
001	pen	100	500	600

after query create:
select  Case When WO_ID > 1 Then '' Else item_code End As item_code,
  Case When WO_ID > 1 Then '' Else item_name End As item_name,
  Case When WO_ID > 1 Then 0 Else value End As value,
  Case When WO_ID > 1 Then 0 Else reward End As reward,
  Case When WO_ID > 1 Then value Else (value+reward) End As total
from (select
  item_code, item_name, value, reward,
  ROW_NUMBER() Over (Partition By item_code Order By item_code) As  WO_ID
from tabelx)

result:

item code	item name	value	reward	total
001	pen	500	500	1000
		600		600
		100		100