题解 | #计算总和#

1. select order_num,sum(item_price * quantity) as total_price
2. from OrderItems
3. group by order_num
4. having total_price >= 1000
5. order by order_num asc

本题不可以直接在 quantity前面加sum函数，item_price不在聚合键里，所以会报错。