title: Datatype model validation
body: <p>In Ruby on Rails, I can't seem to find a validation model method to check for data-type.</p>
  
  <p>I was hoping for something like</p>
  
  <pre><code>validates :name, datatype: :integer
  </code></pre>
  
  <p>but there is nothing on <a href="http://guides.rubyonrails.org/testing.html" rel="nofollow">http://guides.rubyonrails.org/testing.html</a></p>
  
  <p>If such a test not required? Is it because the database engine (mysql or whatever) itself would reject information with a wrong data-type?</p>