title: Check if record exists from controller in Rails
body: <p>In my app a User can create a Business. When they trigger the <code>index</code> action in my <code>BusinessesController</code> I want to check if a Business is related to the <code>current_user.id</code>:</p>
  
  <ul>
  <li>If yes: display the business. </li>
  <li>If no: redirect to the <code>new</code> action. </li>
  </ul>
  
  <p>I was trying to use this:</p>
  
  <pre><code>if Business.where(:user_id =&gt; current_user.id) == nil
    # no business found
  end
  </code></pre>
  
  <p>But it always returns true even when the business doesn't exist...</p>
  
  <p><strong>How can I test if a record exists in my database?</strong></p>