题解 | #计算总和#
计算总和
https://www.nowcoder.com/practice/d8a624021183454586da94d280cc8046
使用having条件语句，附加SQL执行的顺序：
From..... → where条件语句 → group by 分组 → sum、avg等聚合函数计算 → having条件语句 → order by 排序语句
select order_num, sum(item_price * quantity) as total_price from OrderItems group by order_num having total_price >= 1000 order by order_num
