Grouping by week/month/etc & ActiveRecord?

Question

I\'m doing some statics calculation in my product. A user has performed a number of operations, let\'s say posted comments. I want to be able to show them how many comment

Answer 1

Use group_by

@user.comments.group_by(&:week)

class User < ActiveRecord::Base
  def week
    some_attribute_like_date.strftime('%Y-%W')
  end
end

This will give you a grouped list in the format of YYYY-WW