with tmp as(
    SELECT
        EMP_CODE
        , EMP_LAST_NAME
        , EMP_FIRST_NAME
        , REPLACE(EMP_LAST_NAME || EMP_FIRST_NAME, ' ', '') AS FULLNAME
    FROM
        EMP
    WHERE
        VALID_FLG = '1'
)
, tmp2 as(
    SELECT
        FULLNAME
        , COUNT(EMP_CODE) as count
    FROM
        tmp
    GROUP BY
        FULLNAME
)

SELECT
    EMP_CODE AS CODE
    , EMP_LAST_NAME AS SURNAME
    , EMP_FIRST_NAME AS NAME
FROM
    tmp as t
    INNER JOIN tmp2 as t2
    ON t.FULLNAME = t2.FULLNAME
WHERE
    t2.count >= 2
ORDER BY
    t.FULLNAME ASC
    , CODE ASC
;