title: Laravel Carbon Group by Month
body: <p>Can anyone see what I'm doing wrong? </p>
  
  <p>I'm trying to output all the months but group them so they are unique.</p>
  
  <pre><code>$months = NewsItem::select(DB::raw('MONTH("created_at") as month'))-&gt;groupBy('month')-&gt;get();
  return $months;
  </code></pre>
  
  <p>I'm getting the following back</p>
  
  <pre><code>{"month":null}
  </code></pre>
  
  <p>In my database I have five news articles all created_at 05/01/2017 so it's right that I only get one response but I'm not getting the number of the month back?</p>