링크

JOIN

SELECT J.FLAVOR FROM JULY AS J 
LEFT JOIN FIRST_HALF AS F
ON F.SHIPMENT_ID = J.SHIPMENT_ID
GROUP BY J.FLAVOR
ORDER BY SUM(J.TOTAL_ORDER)+F.TOTAL_ORDER DESC
LIMIT 3

UNION

select FLAVOR
from 
    (SELECT *
    from FIRST_HALF
    union
    SELECT *
    from JULY) a

group by FLAVOR
order by SUM(TOTAL_ORDER) desc
limit 3