题解 | 每个顾客最近一次下单的订单信息

select
    orders.order_id,
    customer_name,
    orders.order_date
from
    (
        select
            customer_id,
            max(order_date) as order_date
        from
            orders
        group by
            customer_id
    ) as t1
    left join orders on t1.order_date = orders.order_date
    and t1.customer_id = orders.customer_id
    left join customers on  customers.customer_id=orders.customer_id
    order by customer_name asc