题解 | #某宝店铺折扣率#
某宝店铺折扣率
https://www.nowcoder.com/practice/3a56f160308441f5a79d8ac8d953e5e7
select
round(sum(sales_price)/sum(amount)*100,2)
from (select
p.item_id,s.sales_price,
s.sales_num*p.tag_price as amount
from product_tb p join sales_tb s
on p.item_id = s.item_id) t
还行 不难
