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