I'm running into a DB related problem in Django that I don't understand.
I define an MPTT model like so:
class Image(MPTTModel):
name = models.CharField(max_length=50)
parent = TreeForeignKey('self', null=True, blank=True, related_name='children')
def __unicode__(self):
return self.name
def rank(self): leaves = self.get_leafnodes() if leaves: rank = leaves[0].get_level() - self.get_level() else: rank = 0 return rank
mptt.register(Image, order_insertion_by=['name'])
Then in my views, I attempt a few statements with the model, and I get an OperationalError.
def index(request):
if request.method == 'POST':
image_string = request.POST.get('get_image')
index = image_string.find('(')
if index == -1:
parent = image_string
child = None
else:
parent = image_string[0:index]
child = image_string[index+1:len(image_string)-1]
try:
images = Image.objects.all()
image_names = [a.name for a in images]
except Image.DoesNotExist:
return render(request, 'images_app/index.html', {'images':[]})
else:
parent_model = Image(name=parent)
parent_model.save()
child_model = Image(name=child, parent=parent_model)
child_model.save()
return render(request, 'images_app/index.html', {'images':images})
I'm not sure if this is a problem with my view or the way I'm defining the model. According to my understanding, the 'try' expression should make it so that if the code doesn't evaluate, it will simply skip to the exception. Why doesn't this go straight to the exception?
Traceback:
File "C:\Python27\lib\site-packages\django\core\handlers\base.py" in get_response
114. response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "C:\djangoprojects\images\images_app\views.py" in index
17. if images:
File "C:\Python27\lib\site-packages\django\db\models\query.py" in __nonzero__
100. self._fetch_all()
File "C:\Python27\lib\site-packages\django\db\models\query.py" in _fetch_all
854. self._result_cache = list(self.iterator())
File "C:\Python27\lib\site-packages\django\db\models\query.py" in iterator
220. for row in compiler.results_iter():
File "C:\Python27\lib\site-packages\django\db\models\sql\compiler.py" in results_iter
709. for rows in self.execute_sql(MULTI):
File "C:\Python27\lib\site-packages\django\db\models\sql\compiler.py" in execute_sql
782. cursor.execute(sql, params)
File "C:\Python27\lib\site-packages\django\db\backends\util.py" in execute
69. return super(CursorDebugWrapper, self).execute(sql, params)
File "C:\Python27\lib\site-packages\django\db\backends\util.py" in execute
53. return self.cursor.execute(sql, params)
File "C:\Python27\lib\site-packages\django\db\utils.py" in __exit__
99. six.reraise(dj_exc_type, dj_exc_value, traceback)
File "C:\Python27\lib\site-packages\django\db\backends\util.py" in execute
53. return self.cursor.execute(sql, params)
File "C:\Python27\lib\site-packages\django\db\backends\sqlite3\base.py" in execute
450. return Database.Cursor.execute(self, query, params)
Exception Type: OperationalError at /images/
Exception Value: no such table: images_app_image