title: Not null bug in PHP or not?
body: <p>I don't know if it is a bug or what but here it is. I  <code>var_dump</code> my
   variable <code>status_id</code> it says:</p>
  
  <pre><code>var_dump($status_id);
  string(4) "null"
  </code></pre>
  
  <p>but when I <code>var_dump</code> it says:</p>
  
  <pre><code>var_dump($status_id != NULL);
  bool(true)
  </code></pre>
  
  <p>How can I transform it to null again because I need it to my filter?</p>