题解 | 商品价格排名

select product_id,product_name,type,price
from(
    select product_id,product_name,type,price,dense_rank() over(partition by type order by price desc) as rk
    from product_info
)a
where a.rk<3
order by a.price desc,a.product_name
limit 3

用了row_number后错了，题目应该提醒有并列排名的