WITH t_110 AS(
SELECT 
    t1.PORT_CODE,
    t2.PORT_NAME,
    t1.AMT
FROM IMMIGRATION AS t1
LEFT JOIN PORT AS t2 ON t1.PORT_CODE = t2.PORT_CODE
WHERE KIND_CODE = 110 AND GROUP_CODE = 120
),
t_120 AS(
SELECT 
    PORT_CODE,
    AMT
FROM IMMIGRATION
WHERE KIND_CODE = 120 AND GROUP_CODE = 120
),
t_sum AS(
SELECT
    t_110.PORT_CODE AS '港コード',
    t_110.PORT_NAME AS '港名',
    t_110.AMT AS '入国者数',
    t_120.AMT AS '出国者数',
    t_110.AMT - t_120.AMT AS '差分'
FROM t_110 LEFT JOIN t_120 ON t_110.PORT_CODE = t_120.PORT_CODE
WHERE t_110.AMT > t_120.AMT
)
SELECT *
FROM t_sum
ORDER BY 5 DESC, 1 DESC