题解 | 确定最佳顾客的另一种方式（二）

select cust_name,
    sum(item_price * quantity) as total_price
from OrderItems OI inner join Orders O on OI.order_num = O.order_num inner join Customers C on C.cust_id = O.cust_id
group by
    cust_name
having total_price >= 1000;