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'
        GROUP BY
            REPLACE (EMP_LAST_NAME, ' ', '') || '_' || REPLACE (EMP_FIRST_NAME, ' ', '')
        HAVING
            COUNT(*) > 1
    )
ORDER BY
    REPLACE (EMP_LAST_NAME, ' ', '')
  , EMP_CODE;