SELECT EMP_CODE AS CODE
      ,EMP_LAST_NAME AS SURNAME
      ,EMP_FIRST_NAME AS NAME
  FROM EMP
 WHERE VALID_FLG = '1'
   AND(REPLACE(EMP_LAST_NAME, ' ', '')
      ,REPLACE(EMP_FIRST_NAME, ' ', '')) IN
      (SELECT REPLACE(EMP_LAST_NAME, ' ', '') 
             ,REPLACE(EMP_FIRST_NAME, ' ', '') 
         FROM EMP
        WHERE VALID_FLG = '1'
      )
 ORDER BY SURNAME
         ,NAME
         ,CODE
;