title: django null and empty string
body: <p>I find that when I insert nothing of a string <code>form field</code> through a form it captures it as an empty string <code>''</code>. </p>
  
  <p>However when I insert nothing of an integer <code>form field</code> through a form it captures it as <code>[null]</code>.</p>
  
  <p>Is this good practice? Should the string be <code>null</code> as well in the db?</p>