题解 | #返回每个顾客不同订单的总金额#

select
    t.cust_id,
    sum(t2.quantity * t2.item_price) as total_ordered
from
    Orders t,
    OrderItems t2
where
    t.order_num = t2.order_num
GROUP BY
    t.cust_id
ORDER BY
    total_ordered DESC
#我们需要一个顾客 ID 列表，其中包含他们已订购的总金额