Changes between Initial Version and Version 1 of Ticket #24123

Timestamp:

Jan 11, 2015, 10:51:23 AM (9 years ago)

Author:

Markus Holtermann

Comment:

I created a sample project to replicate the error: ​https://github.com/MarkusH/django-ticket-triage/tree/bug24123

To replicate the above error for forwards migrations, take a clean database and run

$ python manage.py migrate app_b
Operations to perform:
  Apply all migrations: app_b
Running migrations:
  Applying app_a.0001_initial... OK
  Applying app_a.0002_a2... OK
  Applying app_b.0002_b2... OK
  Applying app_b.0003_b3... OK
$ python manage.py migrate
Operations to perform:
  Apply all migrations: app_a, app_c, app_b
Running migrations:
  Applying app_c.0002_c2... OK
  Applying app_a.0003_a3...

Traceback (most recent call last):
  File "manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "/home/markus/Coding/django/django/core/management/__init__.py", line 338, in execute_from_command_line
    utility.execute()
  File "/home/markus/Coding/django/django/core/management/__init__.py", line 330, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/home/markus/Coding/django/django/core/management/base.py", line 390, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/home/markus/Coding/django/django/core/management/base.py", line 444, in execute
    output = self.handle(*args, **options)
  File "/home/markus/Coding/django/django/core/management/commands/migrate.py", line 213, in handle
    executor.migrate(targets, plan, fake=options.get("fake", False))
  File "/home/markus/Coding/django/django/db/migrations/executor.py", line 73, in migrate
    state = self.apply_migration(state, migration, fake=fake)
  File "/home/markus/Coding/django/django/db/migrations/executor.py", line 110, in apply_migration
    state = migration.apply(state, schema_editor)
  File "/home/markus/Coding/django/django/db/migrations/migration.py", line 110, in apply
    operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
  File "/home/markus/Coding/django/django/db/migrations/operations/models.py", line 59, in database_forwards
    schema_editor.create_model(model)
  File "/home/markus/Coding/django/django/db/backends/schema.py", line 233, in create_model
    definition, extra_params = self.column_sql(model, field)
  File "/home/markus/Coding/django/django/db/backends/schema.py", line 132, in column_sql
    db_params = field.db_parameters(connection=self.connection)
  File "/home/markus/Coding/django/django/db/models/fields/related.py", line 1996, in db_parameters
    return {"type": self.db_type(connection), "check": []}
  File "/home/markus/Coding/django/django/db/models/fields/related.py", line 1987, in db_type
    rel_field = self.related_field
  File "/home/markus/Coding/django/django/db/models/fields/related.py", line 1893, in related_field
    return self.foreign_related_fields[0]
  File "/home/markus/Coding/django/django/db/models/fields/related.py", line 1627, in foreign_related_fields
    return tuple(rhs_field for lhs_field, rhs_field in self.related_fields)
  File "/home/markus/Coding/django/django/db/models/fields/related.py", line 1614, in related_fields
    self._related_fields = self.resolve_related_fields()
  File "/home/markus/Coding/django/django/db/models/fields/related.py", line 1599, in resolve_related_fields
    raise ValueError('Related model %r cannot be resolved' % self.rel.to)
ValueError: Related model 'app_b.B2' cannot be resolved

The plan for the second migrate command is

[
    (<Migration app_c.0002_c2>, False),
    (<Migration app_a.0003_a3>, False),
    (<Migration app_a.0004_a4>, False),
    (<Migration app_c.0003_c3>, False)
]

The initial state is:

  app_a.a1:
  app_a.a2:
  app_c.c1: