SELECT
    IM.PORT_CODE AS 港コード,
    PT.PORT_NAME AS 港名,
    IM.AMT AS 入国者数,
    IMOUT.AMT AS 出国者数,
    (IM.AMT - IMOUT.AMT) AS 差分
FROM 
	IMMIGRATION IM
    INNER JOIN IMMIGRATION IMOUT
        ON IMOUT.PORT_CODE = IM.PORT_CODE
        AND IMOUT.GROUP_CODE = IM.GROUP_CODE
        AND IMOUT.KIND_CODE = '120'
    INNER JOIN PORT PT
        ON PT.PORT_CODE = IM.PORT_CODE
WHERE
	IM.KIND_CODE = '110'
    AND IM.GROUP_CODE = '120'
    AND 差分 > 0
ORDER BY
	差分 DESC
	, IM.PORT_CODE DESC
;