题解 | 每个顾客最近一次下单的订单信息

WITH t1 AS(
    SELECT
        o.customer_id,
        c.customer_name,
        MAX(o.order_date) date1
    FROM orders o
    JOIN customers c ON c.customer_id = o.customer_id
    GROUP BY o.customer_id
)
SELECT
    order_id,
    t1.customer_name,
    t1.date1 order_date
FROM orders o
JOIN t1 ON t1.customer_id = o.customer_id AND t1.date1 = o.order_date
ORDER BY t1.customer_name