with
    e1 as
    (
        select
            EMP_CODE,
            replace(EMP_LAST_NAME, ' ', '')
            || replace(EMP_FIRST_NAME, ' ', '')
            as f_name
        from EMP
        where VALID_FLG = '1'
    ),
    e2 as
    (
        select
            f_name
        from e1
        group by
            f_name
        having
            count(f_name) > 1
        
    )
select
    EMP_CODE as CODE,
    EMP_LAST_NAME as SURNAME,
    EMP_FIRST_NAME as NAME
from
    EMP
left outer join e1 using(EMP_CODE)
where
    (f_name) in e2
order by f_name, EMP_CODE
;