title: Rails 3.2 Model scope date less_than_a_
body: <p>I am trying to create a scope which can find the dataset for example, less_than_a_year, less_than_six_month, in my model through my deadline attribute.</p>
  
  <pre><code>class Goal &lt; ActiveRecord::Base
    attr_accessible :category, :title, :detail, :deadline, :achieve
  
    #need help solving this
    scope :less_than_a_year, where()
  end
  </code></pre>
  
  <p>So it would perform, goal.less_than_a_year and provide a list of data less then a year.
  Thank you.</p>