题解 | #返回购买价格为 10 美元或以上产品的顾客列表#

/*select cust_id
from OrderItems a,Orders b
where a.order_num=b.order_num
and a.item_price>=10;*/

/*select cust_id
from OrderItems a left join Orders b
on a.order_num=b.order_num
where a.item_price>=10;*/

select cust_id
from Orders b
where b.order_num in
(select order_num
from OrderItems
where item_price>=10
) ;