题解 | #返回产品名称和每一项产品的总订单数#
返回产品名称和每一项产品的总订单数
https://www.nowcoder.com/practice/1c64fd9048364a58a8ffa541720359a4
select prod_name,count(order_num) as orders from Products left join OrderItems on Products.prod_id = OrderItems.prod_id group by prod_name order by prod_name
一次成功，较为熟练，这个地方只能left join 如果right则少一行
