Sql 红移-窗口功能-获取每行上一小时的统计数据

我正在尝试根据产品订单编写红移查询。 该表包含存储标识、订单号、订单日期时间、产品订单、订单时间等列。我试图编写的查询将从此表中选择，并且对于每一行，它将包含一些基于该商店前一小时订单的统计信息

目前我可以做一些类似的事情：

SELECT store_id, order_number, order_datetime, products_ordered, order_time,
       (SELECT COUNT(*) FROM mtable WHERE store_id=o.store_id AND order_time BETWEEN (o.order_time - interval '1 hour') AND o.order_time) as prev_num_orders,
       (SELECT AVG(products_ordered) FROM mtable WHERE store_id=o.store_id AND order_time BETWEEN (o.order_time - interval '1 hour') AND o.order_time) as prev_avg_orders
FROM mtable o;

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这台电视机的性能太差了。其中一个主要原因可能是我必须查找前几个小时的订单两次，以获得两个不同的统计数据。有没有办法优化这一点？我认为应该有一个窗口功能，但我不确定。

我没有测试de性能的数据，但当我在红移上遇到类似问题时，我就是这样做的：

    with cte as
    (
    SELECT store_id, order_number, order_datetime, products_ordered, order_time,
    LAG (products_ordered,1) OVER (PARTITION BY store_id ORDER BY order_time) AS prev_products_ordered
    from mtable
    )
    select store_id, order_number, order_datetime, products_ordered, order_time,
    count(*) as prev_num_orders, avg(prev_products_ordered) as prev_avg_orders 
from cte
    group by store_id, order_number, order_datetime, products_ordered, order_time

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对于这种情况，我想不出有效的窗口范围，因为值范围是唯一的公共因素。 由于Redshift在大型数据集上非常出色，我建议以下解决方案：

SELECT store_id, 
       order_number, 
       order_datetime, 
       products_ordered, 
       order_time, 
       COUNT(prev_orders.store_id) prev_num_orders,
       AVG(prev_orders.products_ordered)  prev_avg_orders
FROM mtable o
left join mtable prev_orders on prev_orders.store_id=o.store_id 
                            AND prev_orders.order_time BETWEEN (o.order_time - interval '1 hour') AND o.order_time 
--and o.order_number != prev_orders.order_number
group by store_id, 
       order_number, 
       order_datetime, 
       products_ordered, 
       order_time;

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请注意，prev_num_orders和prev_avg_orders列统计信息也将包括当前订单。要从统计数据中删除当前订单，请从SQL语句中取消注释订单号比较行。

示例数据和所需结果将非常有用。