title: Multiple LEFT JOIN statements on the same table
body: <p>I'm trying to LEFT JOIN on the same table multiple times, to get all the values of the specific topics. It works like I thought it would, see: <a href="http://sqlfiddle.com/#!9/9cda67/4" rel="nofollow">http://sqlfiddle.com/#!9/9cda67/4</a></p>
  
  <p>However, using the above fiddle, the database returns a single row for each different course. I'd like to group them, using <code>GROUP BY PersonID</code>, but then it would only take the first value (a 6 for Math) and a <code>(null)</code> value for all the other columns. See: <a href="http://sqlfiddle.com/#!9/9cda67/5" rel="nofollow">http://sqlfiddle.com/#!9/9cda67/5</a></p>
  
  <p>What do I need to change so that I get single row per Person, with all the grades filled in into their respective columns (when available)?</p>