SELECT
  i.PORT_CODE 港コード,
  PORT_NAME 港名,
  SUM(CASE WHEN i.KIND_CODE = 110 THEN AMT ELSE 0 END) 入国者数,
  SUM(CASE WHEN i.KIND_CODE = 120 THEN AMT ELSE 0 END) 出国者数,
  SUM(CASE WHEN i.KIND_CODE = 110 THEN AMT ELSE 0 END) - SUM(CASE WHEN i.KIND_CODE = 120 THEN AMT ELSE 0 END) 差分
FROM
  IMMIGRATION i
INNER JOIN PORT p ON i.PORT_CODE = p.PORT_CODE
GROUP BY i.PORT_CODE
HAVING 入国者数 > 出国者数
ORDER BY 差分 DESC, i.PORT_CODE DESC;