select
    p.PORT_CODE AS 港コード,
    p.PORT_NAME AS 港名,
    SUM(CASE WHEN i.KIND_CODE = 110 THEN i.AMT ELSE 0 END) AS 入国者数,
    SUM(CASE WHEN i.KIND_CODE = 120 THEN i.AMT ELSE 0 END) AS 出国者数,
    ABS(SUM(CASE WHEN i.KIND_CODE = 110 THEN i.AMT ELSE 0 END) - SUM(CASE WHEN i.KIND_CODE = 120 THEN i.AMT ELSE 0 END)) AS 差分
from
    PORT AS p
    inner join IMMIGRATION AS i ON p.PORT_CODE = i.PORT_CODE
where
    i.GROUP_CODE = 120
order by
    差分 desc, p.PORT_CODE desc
;