with wo_space as (
    select
        EMP_CODE CODE,
        REPLACE(EMP_LAST_NAME,' ', '') as SURNAME,
        REPLACE(EMP_FIRST_NAME,' ', '') as NAME,
        (REPLACE(EMP_LAST_NAME,' ', '') || REPLACE(EMP_FIRST_NAME,' ', '')) as FULL
    from 
        EMP
    where
        VALID_FLG = 1
)

select
    code, 
    surname,
    name
from 
    wo_space w1
where
    w1.full in (
        select
            full
        from
            wo_space
        group by
            full
        having
            count(*) > 1
    )
order by
    surname,
    code;