with aaa as (
  select
    replace(EMP_LAST_NAME || EMP_FIRST_NAME , ' ', '') as NAME_VALUE
  from
    EMP
  where
    VALID_FLG = '1'
  group by
    NAME_VALUE
  having
    count(*) > 1
)
select
  EMP_CODE as CODE
 ,EMP_LAST_NAME as SURNAME
 ,EMP_FIRST_NAME as NAME
from
  EMP as main
inner join
  aaa as a
where
  replace(main.EMP_LAST_NAME || main.EMP_FIRST_NAME , ' ', '') = a.NAME_VALUE
order by
  a.NAME_VALUE asc
 ,EMP_CODE asc