title: Django dumpdata unable to serialize existing column
body: <p>I'm getting bit trying to <code>dumpdata</code> from a legacy db i've recently did a reverse engineering using django's <a href="https://docs.djangoproject.com/es/1.9/howto/legacy-databases/" rel="nofollow"><code>inspectdb</code></a>...
  Other than this every query works fine. In MySQL workbench the column exists.
  But when trying to export the data I get:</p>
  
  <pre><code>CommandError: Unable to serialize database: no such column: af_datper.locnac
  </code></pre>
  
  <p>Using <code>traceback</code> doesn't reveal any of my lines affecting (pasted here not to pollute <a href="http://dpaste.com/1DASN1V" rel="nofollow">http://dpaste.com/1DASN1V</a>).</p>
  
  <p>The model field already admits null values for that column and the column does exists in the database (among seeing it with the workbench, <code>inspectdb</code> wouldn't have picked it up...</p>
  
  <p>I honestly don't know what else to do. Any takers?</p>