with im as (
select
    port_code,
    sum(case when KIND_CODE=110 then amt end) as in_,
    sum(case when KIND_CODE=120 then amt end) as out_
from
    immigration
where
    group_code in (120,130)
group by
    port_code
having
    out_<in_
)
select
    im.port_code as `港コード`,
    p.port_name as `港名`,
    in_ as `入国者数`,
    out_ as `出国者数`,
    in_ - out_ as `差分`
from
    im
    inner join
    PORT as p
    on im.PORT_CODE=p.Port_code
order by
    (in_ - out_) desc,
    im.port_code desc