title: Is it possible to define a global scope on Activerecord::Base?
body: <p>I know I can make a module that defines a scope and include this module in a model, following, for example, <a href="https://stackoverflow.com/questions/4699343/rails-is-that-possible-to-define-named-scope-in-a-module">this question's discussion</a>.</p>
  
  <p>But say I have 100 models, all of which have <code>created_at</code> fields. I want to have a scope reading from <code>created_at</code>, but I do not want to manually include the module in all the models. I want to define a scope <strong>globally</strong> for all models.</p>
  
  <p>Seeing how all models inherit from <code>ActiveRecord::Base</code>, I keep looking for ways to define a scope there, but my efforts with using concerns end up with errors.</p>
  
  <pre><code>ActiveRecord::ActiveRecordError: ActiveRecord::Base doesn't belong in a hierarchy descending from ActiveRecord
  </code></pre>