Backwards-incompatible changes

As Django is still in pre-release mode, we haven't yet committed to maintaining backwards compatibility in any APIs. Although we're keeping such changes to a minimum, Django developers should be acutely aware of these changes.

Of course, once we reach our first official release, we'll be strongly committed to backward compatibility.

This page lists all backwards-incompatible changes to Django so far, and the proposed backwards-incompatible changes.

Changes already made

Moved mod_python handler

As of [169], using django.core.handler as a mod_python handler is deprecated. Use django.core.handlers.modpython instead. We will be removing django.core.handler for Django's first release.

Changed ordering syntax

As of [292], syntax used for order_by (in the database API) and ordering (in models) has changed.

Example of old ordering syntax: order_by=[('foo', 'ASC'), ('bar', 'DESC')]

Example of new ordering syntax: order_by=['foo', '-bar']

The old syntax is deprecated, and we'll stop supporting it for Django's first release.

Refactored meta.py

As of [378], django/core/meta.py has been converted to a package, django/core/meta/. If you're using a version of Django from before [378], make sure to delete django/core/meta.pyc and django/core/meta.pyo, if they exist. The existence of those files doesn't pose any known problems, but it's best to clean things up.

Changed edit_inline and edit_inline_type behavior

As of [440], using edit_inline_type in your models is deprecated, in favor of a less-redundant approach that uses edit_inline itself.

Example of old syntax: edit_inline=True, edit_inline_type=meta.TABULAR

Example of new syntax: edit_inline=meta.TABULAR

We'll stop supporting the old syntax for Django's first release.

Changed admin log to store primary keys as TEXT fields, not INTEGER fields

As of [469], the object_id field in django.models.auth.LogEntry is a TextField instead of an IntegerField. We made this change to accomodate non-integer primary keys.

If you're using a Django database installation from before [469] and you want to use non-integer primary keys on an object you edit in the admin site, you'll need to do an ALTER TABLE in your database.

In PostgreSQL:

BEGIN;
ALTER TABLE auth_admin_log RENAME object_id TO object_id_old;
ALTER TABLE auth_admin_log ADD COLUMN object_id TEXT;
UPDATE auth_admin_log SET object_id = object_id_old;
ALTER TABLE auth_admin_log DROP COLUMN object_id_old;
COMMIT;

In MySQL:

ALTER TABLE auth_admin_log MODIFY object_id TEXT;

Possible upcoming changes

Model syntax

This is the big one. Model syntax 'might' be changed dramatically before Django's first release, but this is still under debate. See #122 for full information and discussion.