There are a few ways to solve this problem. However, I think the easiest is to cache the day of the year that the user is born on as an integer. If stored alongside the timestamp we can quickly get a list but properly handle the full birthday elsewhere, s...

You can easily chain scopes together in your models. class Article < ActiveRecord::Base scope :ordered, order('position ASC') scope :published, ordered.where('published = ?', true) scope :for_homepage, published.limit(3) end Article.for_homepage...