题解 | #计算总和#
计算总和
https://www.nowcoder.com/practice/d8a624021183454586da94d280cc8046
select order_num, sum(item_price * quantity) total_price from OrderItems group by order_num having total_price >= 1000 order by order_num asc
- where后面不能直接加聚合函数(分组函数),我们也可以这样记忆:where后面只能跟表中存在的字段。
- having 不能单独使用,必须跟 group by 联合使用。