title: Django : 1048, "Column 'category_id' cannot be null"
body: <p>This is my code:</p>
  
  <pre><code>if ItemSubcategory.objects.filter(name = page_item['slottype']).count() is 0:
      sub_category_set = ItemSubcategory(name = page_item['slottype'])
      sub_category_set.save()
  else:
      sub_category_set = ItemSubcategory.objects.get(name = page_item['slottype'])
  
  ni.sub_category = sub_category_set
  </code></pre>
  
  <p>I wonder why it doesn't allow the newly-made object to be fetched and bound. Besides that, the fact that the object returns null (<code>None</code>) is odd. I should be able to call it instantly after saving it right?</p>