mysql 分组去重排序问题？

Question

一张订单任务表，需要根据order_id字段分组，取每组中的一条数据，同时需要根据updated_at字段进行排序，输出表中的所有字段，能实现吗？

Answer 1

SELECT * FROM order_task a
INNER JOIN (
    SELECT order_id, max(order_task_id) order_task_id 
    FROM order_task 
    GROUP BY order_id
) b ON a.order_task_id = b.order_task_id
order by updated_at

Answer 2

SELECT
    t.order_id,
    MAX( t.updated_at ) updated_at 
FROM
    ( SELECT * FROM order ORDER BY updated_at DESC LIMIT 1000 ) t 
GROUP BY
    order_id