Migrations for auth fails on Django 3.1: KeyError: 'deferrable'

[Raekkeri]

I started a fresh project with Django 3.1. and the latest django-mssql-backend. Running python manage.py migrate auth fails on the "0008" migration:

  Applying auth.0008_alter_user_username_max_length...Traceback (most recent call last):                           File "manage.py", line 22, in <module>
    main()
  File "manage.py", line 18, in main                                                                                 execute_from_command_line(sys.argv)
...
  File "/.../lib/python3.6/site-packages/django/db/backends/base/schema.py", line 572, in alter_field
    old_db_params, new_db_params, strict)
  File "/.../lib/python3.6/site-packages/sql_server/pyodbc/schema.py", line 479, in _alter_field
    self.execute(self._create_unique_sql(model, columns=[old_field.column]))
  File "/.../lib/python3.6/site-packages/sql_server/pyodbc/schema.py", line 863, in execute
    sql = str(sql)
  File "/.../venv/lib/python3.6/site-packages/django/db/backends/ddl_references.py", line 200, in __str__
    return self.template % self.parts
KeyError: 'deferrable'

While experimenting a little, downgrading to Django 2.2 fixed the issue with the problematic migrations, and after upgrading back to 3.1 I was able to run the remaining migrations (those that are new in Django 3). Digging into the code base the problem seems quite straightforward: the django.db.backends.ddl_references.Statement seems indeed to expect a deferrable keyword argument, and after hacking the source code so that an empty string was given as deferrable, the migrations worked just fine. Unfortunately I'm not familiar with mssql or this library, and can't simply attempt a pull request for this.

[jalpar]

I have the same issue with Django 3.1.
Migrations work fine with Django 3.0.

I also found this on stackoverflow:

https://stackoverflow.com/questions/63282351/django-and-azure-sql-key-error-deferrable-when-start-migrate-command

[cristian-home]

I had the same problem in Django 3.1 with a custom user model, when I executed the migration I got the following error:

  Applying contenttypes.0001_initial... OK
  Applying contenttypes.0002_remove_content_type_name... OK
  Applying auth.0001_initial... 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 auth.0007_alter_validators_add_error_messages... OK
  Applying auth.0008_alter_user_username_max_length... OK
  Applying auth.0009_alter_user_last_name_max_length... OK
  Applying auth.0010_alter_group_name_max_length...Traceback (most recent call last):
  File "./manage.py", line 22, in <module>
    main()
  File "./manage.py", line 18, in main
    execute_from_command_line(sys.argv)
  File "/home/cristian/.virtualenvs/SIM2/lib/python3.8/site-packages/django/core/management/__init__.py", line 401, in execute_from_command_line
    utility.execute()
  File "/home/cristian/.virtualenvs/SIM2/lib/python3.8/site-packages/django/core/management/__init__.py", line 395, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/home/cristian/.virtualenvs/SIM2/lib/python3.8/site-packages/django/core/management/base.py", line 330, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/home/cristian/.virtualenvs/SIM2/lib/python3.8/site-packages/django/core/management/base.py", line 371, in execute
    output = self.handle(*args, **options)
  File "/home/cristian/.virtualenvs/SIM2/lib/python3.8/site-packages/django/core/management/base.py", line 85, in wrapped
    res = handle_func(*args, **kwargs)
  File "/home/cristian/.virtualenvs/SIM2/lib/python3.8/site-packages/django/core/management/commands/migrate.py", line 243, in handle
    post_migrate_state = executor.migrate(
  File "/home/cristian/.virtualenvs/SIM2/lib/python3.8/site-packages/django/db/migrations/executor.py", line 117, in migrate
    state = self._migrate_all_forwards(state, plan, full_plan, fake=fake, fake_initial=fake_initial)
  File "/home/cristian/.virtualenvs/SIM2/lib/python3.8/site-packages/django/db/migrations/executor.py", line 147, in _migrate_all_forwards
    state = self.apply_migration(state, migration, fake=fake, fake_initial=fake_initial)
  File "/home/cristian/.virtualenvs/SIM2/lib/python3.8/site-packages/django/db/migrations/executor.py", line 227, in apply_migration
    state = migration.apply(state, schema_editor)
  File "/home/cristian/.virtualenvs/SIM2/lib/python3.8/site-packages/django/db/migrations/migration.py", line 124, in apply
    operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
  File "/home/cristian/.virtualenvs/SIM2/lib/python3.8/site-packages/django/db/migrations/operations/fields.py", line 236, in database_forwards
    schema_editor.alter_field(from_model, from_field, to_field)
  File "/home/cristian/.virtualenvs/SIM2/lib/python3.8/site-packages/django/db/backends/base/schema.py", line 571, in alter_field
    self._alter_field(model, old_field, new_field, old_type, new_type,
  File "/home/cristian/.virtualenvs/SIM2/lib/python3.8/site-packages/sql_server/pyodbc/schema.py", line 479, in _alter_field
    self.execute(self._create_unique_sql(model, columns=[old_field.column]))
  File "/home/cristian/.virtualenvs/SIM2/lib/python3.8/site-packages/sql_server/pyodbc/schema.py", line 861, in execute
    sql = str(sql)
  File "/home/cristian/.virtualenvs/SIM2/lib/python3.8/site-packages/django/db/backends/ddl_references.py", line 200, in __str__
    return self.template % self.parts
KeyError: 'deferrable'

Downgrading to Django 3.0.x made the migration work properly.

[shakthifuture]

Any solution? I need to use Django 3.1, I can't downgrade

[franzejr]

Got the same error on Django 3.1.1.

[franzejr]

I confirm downgrading to Django 3.0.10 fixes the issue.

[tietjen-douglas]

I have also come across this issue with Django 3.1. I hope a fix can come soon.

[mriffey]

I also see this issue. Moving to 3.0 temporarily worked around it though.

[dot-legal]

Bumping this issue up, I would love to use Django 3.1 with this. Thanks!

Same problem for me on Django 3.1.4

[kumbhagirishiva]

Same problem for me on Django 3.1.4
Is their any solution to this, I was downgraded to 3.0.6 also but not solved.
Any body knows about this error ,please give solution

[Lazloo]

Same problem on my site but, only when I use django-mssql-backend

[dcleveng]

I'm using django-mssql-backend and ran in to this issue on two separate occasions. Downgrading fixed the issue the first time around, but here's what I did to work around it the second time:

I found that removing unique=True from the migration file on one of the fields I was modifying allowed the migration to proceed without downgrading Django.