解题
连接各表,窗口函数求出排名
select o.order_date, o.seller_id, i.item_brand, u.favorite_brand,
rank() over...Samsung", "HP", 1],
["2019-08-05", 4, "Lenovo", "HP", 2]]}
选出 rnk = 2 的,再左连接 所有用户的 id
# Write your MySQL...(
select o.order_date, o.seller_id, i.item_brand, u.favorite_brand,
rank() over