删除我的数据库并尝试应用新的迁移后，我收到了这个错误，说 django.db.migrations.exceptions.NodeNotFoundError

Question

Am trying to apply a migration to a new database but I keep getting this error, I have deleted all migration files in my old database and also files in the apps. when I tried applying migrations to a new database or running python manage.py runserver then I get this error..? I wonder what might be the problem. am using Django 3.1.1

E:\All django project\Real-Estate-Django-Web-App-master>manage.py migrate
Traceback (most recent call last):
  File "E:\All django project\Real-Estate-Django-Web-App-master\manage.py", line 15, in <module>
    execute_from_command_line(sys.argv)
  File "C:\Python38\lib\site-packages\django\core\management\__init__.py", line 401, in execute_from_command_line
    utility.execute()
  File "C:\Python38\lib\site-packages\django\core\management\__init__.py", line 395, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "C:\Python38\lib\site-packages\django\core\management\base.py", line 330, in run_from_argv
    self.execute(*args, **cmd_options)
  File "C:\Python38\lib\site-packages\django\core\management\base.py", line 371, in execute
    output = self.handle(*args, **options)
  File "C:\Python38\lib\site-packages\django\core\management\base.py", line 85, in wrapped
    res = handle_func(*args, **kwargs)
  File "C:\Python38\lib\site-packages\django\core\management\commands\migrate.py", line 92, in handle
    executor = MigrationExecutor(connection, self.migration_progress_callback)
  File "C:\Python38\lib\site-packages\django\db\migrations\executor.py", line 18, in __init__
    self.loader = MigrationLoader(self.connection)
  File "C:\Python38\lib\site-packages\django\db\migrations\loader.py", line 53, in __init__
    self.build_graph()
  File "C:\Python38\lib\site-packages\django\db\migrations\loader.py", line 255, in build_graph
    self.graph.validate_consistency()
  File "C:\Python38\lib\site-packages\django\db\migrations\graph.py", line 195, in validate_consistency
    [n.raise_error() for n in self.node_map.values() if isinstance(n, DummyNode)]
  File "C:\Python38\lib\site-packages\django\db\migrations\graph.py", line 195, in <listcomp>
    [n.raise_error() for n in self.node_map.values() if isinstance(n, DummyNode)]
  File "C:\Python38\lib\site-packages\django\db\migrations\graph.py", line 58, in raise_error
    raise NodeNotFoundError(self.error_message, self.key, origin=self.origin)
django.db.migrations.exceptions.NodeNotFoundError: Migration auth.0013_user_following dependencies reference nonexistent parent node ('account', '0003_contact')

Answer 1

Well! I was finally able to fix this problem by first uninstalling Django on my virtual env and then redo the installation, but the problem had still persisted, so I just followed my intuition by deleting the whole virtual env, I did the installation of virtualenv and then installed Django and it worked, perfectly. Thank you to all who had tried to help, I really appreciated your answers.

Answer 2

The auth.0013_user_following migration requires the 0003_contact migration which is missing.

Try removing all migrations from all apps and set a new database.

Answer 3

Based on the solution provided by Abubakari UmarblacKrussain Uma, I noticed that packages linked to my virtual environment file were missing/corrupted. When I checked it against my requirements.text file, I noticed that the Django package was replaced by django 2.2.27 (django lowercase), and an entry -jango 3.1.3 was added. I manually edited the requirements.txt file to remove the -jango 3.1.3 entry and replace the django 2.2.27 with Django 3.1.3 and reloaded the virtual environment from requirements.txt . This resolved the error. For good measure I re-generated the requirements.txt file for the virtual environment.