title: Laravel Eloquent - sync() on a Morph relationship
body: <p>It seems like there is no <code>sync()</code> function for morph tables on Laravel. </p>
  
  <p>I have two tables <code>avails</code> and <code>questions</code>. <code>questions</code> is a <code>morphMany</code> table. I want to use the sync command, and this is what I did:</p>
  
  <pre><code>Avail::find($id)-&gt;questions()-&gt;sync($some_ids);
  </code></pre>
  
  <p>This gives me the following error:</p>
  
  <blockquote>
    <p>Call to undefined method Illuminate\Database\Query\Builder::sync()</p>
  </blockquote>
  
  <p>So is there a way to get <code>sync</code> to work or am I just not doing this right?</p>