select
a.EMP_CODE as CODE,
a.EMP_LAST_NAME as SURNAME,
a.EMP_FIRST_NAME as NAME
  from EMP a
 where a.VALID_FLG = '1'
   and exists(select 1 
                from EMP b
               where b.VALID_FLG = '1'
                 and replace(a.EMP_LAST_NAME,' ','')
                   = replace(b.EMP_LAST_NAME,' ','')
                 and replace(a.EMP_FIRST_NAME,' ','')
                   = replace(b.EMP_FIRST_NAME,' ','')
                 and a.EMP_CODE != b.EMP_CODE)
order by replace(a.EMP_LAST_NAME ,' ',''),
         replace(a.EMP_FIRST_NAME,' ',''),a.EMP_CODE