Error running shop.0007_notification_recipient migration using MySQL.

Hi,

I am getting this error while trying to migrate an existing project to django-shop 0.11 - using MySQL. This only happens trying to migrate existing data, starting a fresh database works fine.

Applying shop.0007_notification_recipient...Traceback (most recent call last):
  File "manage.py", line 23, in <module>
    execute_from_command_line(sys.argv)
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/core/management/__init__.py", line 367, in execute_from_command_line
    utility.execute()
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/core/management/__init__.py", line 359, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/core/management/base.py", line 294, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/core/management/base.py", line 345, in execute
    output = self.handle(*args, **options)
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/core/management/commands/migrate.py", line 204, in handle
    fake_initial=fake_initial,
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/db/migrations/executor.py", line 115, in migrate
    state = self._migrate_all_forwards(state, plan, full_plan, fake=fake, fake_initial=fake_initial)
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/db/migrations/executor.py", line 145, in _migrate_all_forwards
    state = self.apply_migration(state, migration, fake=fake, fake_initial=fake_initial)
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/db/migrations/executor.py", line 244, in apply_migration
    state = migration.apply(state, schema_editor)
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/db/migrations/migration.py", line 129, in apply
    operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/db/migrations/operations/fields.py", line 204, in database_forwards
    schema_editor.alter_field(from_model, from_field, to_field)
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/db/backends/base/schema.py", line 495, in alter_field
    old_db_params, new_db_params, strict)
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/db/backends/base/schema.py", line 732, in _alter_field
    self.execute(self._create_fk_sql(model, new_field, "_fk_%(to_table)s_%(to_column)s"))
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/db/backends/base/schema.py", line 112, in execute
    cursor.execute(sql, params)
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/db/backends/utils.py", line 79, in execute
    return super(CursorDebugWrapper, self).execute(sql, params)
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/db/utils.py", line 94, in __exit__
    six.reraise(dj_exc_type, dj_exc_value, traceback)
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/django/db/backends/mysql/base.py", line 110, in execute
    return self.cursor.execute(query, args)
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/MySQLdb/cursors.py", line 205, in execute
    self.errorhandler(self, exc, value)
  File "/Users/dino/.virtualenvs/ecuga.com/lib/python2.7/site-packages/MySQLdb/connections.py", line 36, in defaulterrorhandler
    raise errorclass, errorvalue
django.db.utils.IntegrityError: (1452, 'Cannot add or update a child row: a foreign key constraint fails (`ecuga_site`.`#sql-2a3_2e2`, CONSTRAINT `shop_notification_recipient_id_81184845_fk_auth_user_id` FOREIGN KEY (`recipient_id`) REFERENCES `auth_user` (`id`))')

[jrief]

Hugh, finally. Sorry for that and thanks for your patience.

I had to fix this model settings, because having an PositiveIntegerField holding either a pseudo foreign key, or a magic value, was a really bad idea. Therefore this change.

[dinoperovic]

Yes it works now! Thanks.