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