id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
24725	"""ProgrammingError: relation does not exist"" when renaming many-to-many target model"	Danilo Bargen	Markus Holtermann	"To demonstrate this bug, I created a Github repository: https://github.com/dbrgn/django18-migration-bug You can see each step in the commit log.

When I run the migrations for that project in a clean Postgres database, I get an exception. You can run ""reproduce.sh"" to reproduce (d'oh!).

{{{
$ dropdb dj18
$ createdb dj18
$ ./manage.py migrate
Operations to perform:
  Synchronize unmigrated apps: staticfiles, messages
  Apply all migrations: admin, debug, contenttypes, auth, sessions
Synchronizing apps without migrations:
  Creating tables...
    Running deferred SQL...
  Installing custom SQL...
Running migrations:
  Rendering model states... DONE
  Applying contenttypes.0001_initial... OK
  Applying auth.0001_initial... OK
  Applying admin.0001_initial... OK
  Applying contenttypes.0002_remove_content_type_name... OK
  Applying auth.0002_alter_permission_name_max_length... OK
  Applying auth.0003_alter_user_email_max_length... OK
  Applying auth.0004_alter_user_username_opts... OK
  Applying auth.0005_alter_user_last_login_null... OK
  Applying auth.0006_require_contenttypes_0002... OK
  Applying debug.0001_initial... OK
  Applying debug.0002_auto_20150429_1317...Traceback (most recent call last):
  File ""./manage.py"", line 10, in <module>
    execute_from_command_line(sys.argv)
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/core/management/__init__.py"", line 338, in execute_from_command_line
    utility.execute()
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/core/management/__init__.py"", line 330, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/core/management/base.py"", line 390, in run_from_argv
    self.execute(*args, **cmd_options)
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/core/management/base.py"", line 441, in execute
    output = self.handle(*args, **options)
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/core/management/commands/migrate.py"", line 221, in handle
    executor.migrate(targets, plan, fake=fake, fake_initial=fake_initial)
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/db/migrations/executor.py"", line 110, in migrate
    self.apply_migration(states[migration], migration, fake=fake, fake_initial=fake_initial)
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/db/migrations/executor.py"", line 147, in apply_migration
    state = migration.apply(state, schema_editor)
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/db/migrations/migration.py"", line 115, in apply
    operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/db/migrations/operations/models.py"", line 217, in database_forwards
    to_field,
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/db/backends/base/schema.py"", line 469, in alter_field
    return self._alter_many_to_many(model, old_field, new_field, strict)
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/db/backends/base/schema.py"", line 780, in _alter_many_to_many
    new_field.rel.through._meta.get_field(new_field.m2m_reverse_field_name()),
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/db/backends/base/schema.py"", line 484, in alter_field
    old_db_params, new_db_params, strict)
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/db/backends/base/schema.py"", line 715, in _alter_field
    self.execute(self._create_fk_sql(model, new_field, ""_fk_%(to_table)s_%(to_column)s""))
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/db/backends/base/schema.py"", line 107, in execute
    cursor.execute(sql, params)
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/db/backends/utils.py"", line 79, in execute
    return super(CursorDebugWrapper, self).execute(sql, params)
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/db/backends/utils.py"", line 64, in execute
    return self.cursor.execute(sql, params)
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/db/utils.py"", line 97, in __exit__
    six.reraise(dj_exc_type, dj_exc_value, traceback)
  File ""/home/danilo/.virtualenvs/django18-migration-bug/lib/python2.7/site-packages/django/db/backends/utils.py"", line 64, in execute
    return self.cursor.execute(sql, params)
django.db.utils.ProgrammingError: relation ""debug_spam"" does not exist
}}}

This only happens in Django 1.8, with 1.7.7 the migrations run fine."	Bug	closed	Migrations	1.8	Release blocker	fixed	migrations		Ready for checkin	1	0	0	0	0	0