SELECT EMP_CODE CODE,EMP_LAST_NAME SURNAME,EMP_FIRST_NAME NAME 
FROM EMP 
WHERE VALID_FLG=1 
    AND REPLACE (EMP_LAST_NAME || EMP_FIRST_NAME, ' ', '') IN ( 
        SELECT
            REPLACE (EMP_LAST_NAME || EMP_FIRST_NAME, ' ', '') AS EMP_NAME 
        FROM
            EMP 
        WHERE
            VALID_FLG =1
        GROUP BY
            EMP_NAME 
        HAVING
            COUNT(*) >= 2
    ) 
ORDER BY
    REPLACE (EMP_LAST_NAME || EMP_FIRST_NAME, ' ', '') ASC
    , EMP_CODE ASC;