with TBL as (
select
    E1.EMP_CODE as CODE
    ,E1.EMP_LAST_NAME as SURNAME
    ,E1.EMP_FIRST_NAME as NAME
from
    EMP E1
    inner join
        EMP E2
        on
            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
            and
            E1.VALID_FLG=E2.VALID_FLG
where
    E1.VALID_FLG='1'
order by 
    replace(E1.emp_last_name, ' ', '')
    || replace(E1.emp_first_name, ' ', '')
    ,1
)

select distinct 
    CODE
    ,SURNAME
    ,NAME
from
    TBL
;