Question

为窗口分析函数制作“框架”时，可以指定要“回顾”的文字行数。例如，以下将获得一个家庭每周26周的销售额。

,sum(sales) over (partition by household_id order by week_id rows 26 preceding) as x26

但是......如果你想用偏移量回顾（或向前）怎么办？例如，如果是第n周，您想要在第n周前8周结束的26周的销售额？在我打字的时候，我突然意识到我可能会部分地这样做。即，

 ,sum(sales) over (partition by household_id order by week_id rows 34 preceding) as x34
 ,sum(sales) over (partition by household_id order by week_id rows 8 preceding) as x8

...并trailing26_offeset8 = x34 - x8

嗯......很高兴我问道。但无论如何，你知道是否有一个功能可以让我在分区规范本身中指定偏移量吗？

谢谢！

Answer 1

尝试在窗口范围规范中使用between：

sum(sales) over (partition by household_id
                 order by week_id
                 rows between 34 preceding and 8 preceding
                ) as x34

Netezza SQL：在窗口框架中指定偏移量

1 个答案: