SELECT 
A.PORT_CODE AS "港コード"
,C.PORT_NAME AS 港名
,A.AMT AS 入国者数
,B.AMT AS 出国者数
,A.AMT-B.AMT AS 差分
FROM IMMIGRATION A
INNER JOIN  IMMIGRATION B
ON A.PORT_CODE = B.PORT_CODE
INNER JOIN PORT C ON A.PORT_CODE = C.PORT_CODE
WHERE A.GROUP_CODE ='120'
AND A.KIND_CODE ='110'
AND B.GROUP_CODE ='120'
AND B.KIND_CODE ='120'
AND A.AMT-B.AMT >0
order by 5 DESC,1 DESC