SELECT EMP_CODE AS CODE, EMP_LAST_NAME AS SURNAME, EMP_FIRST_NAME AS NAME FROM EMP E1
WHERE VALID_FLG='1' AND EXISTS (
  SELECT 1 FROM EMP E2
    WHERE VALID_FLG='1' AND REPLACE(E1.EMP_LAST_NAME, ' ', '') = REPLACE(E2.EMP_LAST_NAME, ' ', '') AND REPLACE(E1.EMP_FIRST_NAME, ' ', '') = REPLACE(E2.EMP_FIRST_NAME, ' ', '') AND E1.EMP_CODE <> E2.EMP_CODE)
ORDER BY REPLACE(E1.EMP_LAST_NAME, ' ', ''), REPLACE(E1.EMP_FIRST_NAME, ' ', ''), EMP_CODE;