SELECT
	p.PORT_CODE AS 港コード
	,p.PORT_NAME AS 港名
	,i0.AMT AS 入国者数
	,i1.AMT AS 出国者数
	,(i0.AMT - i1.AMT) AS 差分
FROM
	IMMIGRATION AS i0
	INNER JOIN IMMIGRATION AS i1
		ON i1.PORT_CODE = i0.PORT_CODE
		AND i1.GROUP_CODE = i0.GROUP_CODE
	INNER JOIN PORT AS p
		ON p.PORT_CODE = i0.PORT_CODE
WHERE
	i0.KIND_CODE= '110'
	AND i0.GROUP_CODE= '120'
	AND i0.AMT > i1.AMT 
ORDER BY
	差分 DESC
	,i0.PORT_CODE DESC;