是否可以直接在ActiveRecord/Rails中按小时/分钟/季度小时进行分组? [英] Is it possible to group by hour/minute/quarter hour directly in ActiveRecord/Rails?

问题描述

我想按小时/天，甚至是四分之一小时对数据进行分组.

I want to group my data by the hour/day possibly even to the quarter hour.

我可以直接在ActiveRecord中执行此操作吗?还是应该只获取所有数据并手动进行汇总?

Can I do this directly in ActiveRecord or should I just grab all the data and do the aggregation manually?

Table "Checkin":
  Time    NumBikes ChangeBikes
  09:00   5         5
  09:05   6         1
  09:10   10        4
  10:00   6         4
  10:05   8         2
  10:10   16        8

Looking to get something like:
  Time   Sum(ChangeBikes) 
  09:00   10
  10:00   14

提前谢谢克里斯.

推荐答案

我寻求的解决方案是在我所追求的时间段内在表上创建其他列.对于上面的示例，我将添加一个Time_Hour列，并将时间四舍五入到适当的小时.然后，我可以对该列进行分组/分析，以按小时获取统计信息.

The solution I went for was to create additional columns on the table for the time periods I am after. For the example above, I would add a Time_Hour column with the time rounded down to the appropriate hour. I could then do groupings/analysis on that column to get stats by the hour.

这篇关于是否可以直接在ActiveRecord/Rails中按小时/分钟/季度小时进行分组?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！