题解 | 确定哪些订单购买了 prod_id 为 BR01 的产品（一）

SELECT
    cust_id,
    order_date
FROM
    Orders
WHERE
    order_num IN (
        SELECT
            order_num
        FROM
            OrderItems
        WHERE
            prod_id = 'BR01'
    )
ORDER BY
    order_date;

select
    cust_id,
    order_date
from
    Orders o,
    OrderItems oi
where
    prod_id = 'BR01'
    and o.order_num = oi.order_num
order by
    order_date