django makemigrations error “no such column”

Question

I am developing a Django project with REST Framework. It all worked well before, but all of a sudden I can't add any new model fields: If I add any new field even if the most simple one like this:

    def_episode = models.IntegerField(blank=True, null=True)

And manage.py makemigrations , this will happen:

Traceback (most recent call last):
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\db\backends\utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\db\backends\sqlite3\base.py", line 383, in execute
    return Database.Cursor.execute(self, query, params)
sqlite3.OperationalError: no such column: novelrecorder_novel.def_episode

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "manage.py", line 21, in <module>
    main()
  File "manage.py", line 17, in main
    execute_from_command_line(sys.argv)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\core\management\__init__.py", line 381, in execute_from_command_line
    utility.execute()
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\core\management\__init__.py", line 375, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\core\management\base.py", line 323, in run_from_argv
    self.execute(*args, **cmd_options)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\core\management\base.py", line 361, in execute
    self.check()
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\core\management\base.py", line 390, in check
    include_deployment_checks=include_deployment_checks,
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\core\management\base.py", line 377, in _run_checks
    return checks.run_checks(**kwargs)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\core\checks\registry.py", line 72, in run_checks
    new_errors = check(app_configs=app_configs)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\core\checks\urls.py", line 40, in check_url_namespaces_unique
    all_namespaces = _load_all_namespaces(resolver)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\core\checks\urls.py", line 57, in _load_all_namespaces
    url_patterns = getattr(resolver, 'url_patterns', [])
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\utils\functional.py", line 80, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\urls\resolvers.py", line 584, in url_patterns
    patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\utils\functional.py", line 80, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\urls\resolvers.py", line 577, in urlconf_module
    return import_module(self.urlconf_name)
  File "C:\Users\daichou\AppData\Local\Programs\Python\Python37-32\lib\importlib\__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1006, in _gcd_import
  File "<frozen importlib._bootstrap>", line 983, in _find_and_load
  File "<frozen importlib._bootstrap>", line 967, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 677, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 728, in exec_module
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "D:\MyProjects\Python\Django\env\mysite\mysite\urls.py", line 19, in <module>
    from novelrecorder import views
  File "D:\MyProjects\Python\Django\env\mysite\novelrecorder\views.py", line 19, in <module>
    from novelrecorder.serializers import NovelSerializer, NovelReadOnlySerializer, \
  File "D:\MyProjects\Python\Django\env\mysite\novelrecorder\serializers.py", line 241, in <module>
    class CharacterCreateSerializer(CharacterSerializer):
  File "D:\MyProjects\Python\Django\env\mysite\novelrecorder\serializers.py", line 245, in CharacterCreateSerializer
    param_key_field_name='novel_id'))
  File "D:\MyProjects\Python\Django\env\mysite\novelrecorder\yd_fields.py", line 23, in __init__
    super().__init__(**kwargs)
  File "D:\MyProjects\Python\Django\env\mysite\novelrecorder\yd_fields.py", line 10, in __init__
    super().__init__(**kwargs)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\rest_framework\fields.py", line 1404, in __init__
    self.choices = choices
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\rest_framework\fields.py", line 1440, in _set_choices
    self.grouped_choices = to_choices_dict(choices)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\rest_framework\fields.py", line 142, in to_choices_dict
    for choice in choices:
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\db\models\query.py", line 274, in __iter__
    self._fetch_all()
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\db\models\query.py", line 1242, in _fetch_all
    self._result_cache = list(self._iterable_class(self))
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\db\models\query.py", line 55, in __iter__
    results = compiler.execute_sql(chunked_fetch=self.chunked_fetch, chunk_size=self.chunk_size)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\db\models\sql\compiler.py", line 1100, in execute_sql
    cursor.execute(sql, params)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\db\backends\utils.py", line 99, in execute
    return super().execute(sql, params)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\db\backends\utils.py", line 67, in execute
    return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\db\backends\utils.py", line 76, in _execute_with_wrappers
    return executor(sql, params, many, context)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\db\backends\utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\db\utils.py", line 89, in __exit__
    raise dj_exc_value.with_traceback(traceback) from exc_value
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\db\backends\utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "D:\MyProjects\Python\Django\env\venv\lib\site-packages\django\db\backends\sqlite3\base.py", line 383, in execute
    return Database.Cursor.execute(self, query, params)
django.db.utils.OperationalError: no such column: novelrecorder_novel.def_episode

Without adding any new fields, everything looks ok and the server works. Tried to remove the field and makemigrations then migrate , "Nothing needs to change or apply"

Parts of settings.py :

INSTALLED_APPS = [
    'novelrecorder.apps.NovelRecorderConfig',
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'django.contrib.sites',
    'rest_framework',
    'gunicorn',
]

MIDDLEWARE = [
    'django.middleware.security.SecurityMiddleware',
    'whitenoise.middleware.WhiteNoiseMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
]

The model I attempted to add a new field model.py :

class Novel(CustomNovelModel):
    author = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.PROTECT, related_name='novel_author')
    name = models.CharField(max_length=200)
    is_public = models.BooleanField(default=True)
    def_episode = models.IntegerField(blank=True, null=True)

    class Meta:
        ordering = ['name']
        unique_together = ['author', 'name']

Answer 1

I was searching for a similar problem and came across you question. After reading through my error-log again I noticed that the migrations was stumbling on some frontend and admin code which was causing it to fail.

To 'fix' the issue

1. I temporary commented-out the code in question
2. Ran migrations
3. Deployed everything
4. Uncommented the code

All seems to be fine.

When I'm looking through your log, I'm seeing a package novelrecorder which seems to cause an error. Try commenting-out that code.

Perhaps this helps you or someone else coming across this issue.

Answer 2

Delete db.sqlite3 from ur database and migrations from ur App. Then try to migrate again..