SELECT
    P.PORT_CODE AS 港コード,
    P.PORT_NAME AS 港名,
    I_110.AMT AS 入国者数,
    I_120.AMT AS 出国者数,
    I_110.AMT - I_120.AMT AS 差分
FROM
    IMMIGRATION AS I_110
LEFT JOIN
    PORT AS P ON P.PORT_CODE = I_110.PORT_CODE
INNER JOIN
    IMMIGRATION AS I_120 ON I_120.PORT_CODE = I_110.PORT_CODE AND I_120.GROUP_CODE = 120 AND I_120.KIND_CODE = 120
WHERE
    I_110.GROUP_CODE = 120 AND I_110.KIND_CODE = 110 AND 差分 > 0
ORDER BY
    差分 DESC, P.PORT_CODE DESC
;