title: Counting NULL values in a case statement
body: <p>I have the following SQL Query:</p>
  
  <pre><code>SELECT jobs.ID,  jobs.title,
  SUM(CASE WHEN jobresponses.result = 'true' THEN 1 ELSE 0 END) as True,
  SUM(CASE WHEN jobresponses.result = 'false' THEN 1 ELSE 0 END) as False,
  SUM(CASE WHEN jobresponses.result != 'true' AND jobresponses.result != 'false' THEN 1 ELSE 0 END) as Incomplete
  FROM jobresponses 
  JOIN jobs on jobresponses.jobId = jobs.ID
  WHERE jobs.ID = 1
  GROUP BY jobs.ID, jobs.title
  </code></pre>
  
  <p>The third case expressions is in practice counting values with a <code>result</code> of <code>NULL</code>, but to be safe (between <code>''</code>, <code>undefined</code> and <code>NULL</code>) I wanted to basically have a catch all "other" type field. However, the issue is that the NULL values aren't being counted. See <a href="http://sqlfiddle.com/#!6/dd62e/2" rel="nofollow noreferrer">this</a> SQL Fiddle. </p>