select
    tmp.class_name CLASS,
    tmp.person_name PERSON,
    tmp.amt HOUSEHOLDS
from
(
    select
        *,
        rank() over(partition by class_name order by amt desc) pri
    from HOUSEHOLD
    where 1 = 1
    and person_code != '1'
    and class_code != '01'
)tmp
where tmp.pri = 1
order by 1 asc
;