Fixed #36564 -- Changed DEFAULT_AUTO_FIELD from AutoField to BigAutoField.

docs/intro/reusable-apps.txt

@@ -153,7 +153,6 @@ this. For a small app like polls, this process isn't too difficult.
 
 
        class PollsConfig(AppConfig):
-           default_auto_field = "django.db.models.BigAutoField"
            name = "django_polls"
            label = "polls"
 

docs/ref/checks.txt

@@ -429,7 +429,8 @@ Models
 * **models.E042**: ``<field name>`` cannot be included in the composite
   primary key.
 * **models.W042**: Auto-created primary key used when not defining a primary
-  key type, by default ``django.db.models.AutoField``.
+  key type, by default ``django.db.models.AutoField``. *This check appeared in
+  Django 3.2 - 5.2*.
 * **models.W043**: ``<database>`` does not support indexes on expressions.
 * **models.W044**: ``<database>`` does not support unique constraints on
   expressions.

docs/ref/settings.txt

@@ -1279,11 +1279,16 @@ See also :setting:`NUMBER_GROUPING`, :setting:`THOUSAND_SEPARATOR` and
 ``DEFAULT_AUTO_FIELD``
 ----------------------
 
-Default: ``'``:class:`django.db.models.AutoField`\ ``'``
+Default: ``'``:class:`django.db.models.BigAutoField`\ ``'``
 
 Default primary key field type to use for models that don't have a field with
 :attr:`primary_key=True <django.db.models.Field.primary_key>`.
 
+.. versionchanged:: 6.0
+
+    In older versions, the default value is
+    :class:`django.db.models.AutoField`.
+
 .. admonition:: Migrating auto-created through tables
 
     The value of ``DEFAULT_AUTO_FIELD`` will be respected when creating new

docs/releases/6.0.txt

@@ -458,6 +458,36 @@ Email
   significantly, closely examine any custom subclasses that rely on overriding
   undocumented, internal underscore methods.
 
+``DEFAULT_AUTO_FIELD`` setting now defaults to ``BigAutoField``
+---------------------------------------------------------------
+
+Since Django 3.2 when the :setting:`DEFAULT_AUTO_FIELD` setting was added,
+the default :djadmin:`startproject` template's ``settings.py`` contained::
+
+    DEFAULT_AUTO_FIELD = "django.db.models.BigAutoField"
+
+and the default :djadmin:`startapp` template's ``AppConfig`` contained::
+
+    default_auto_field = "django.db.models.BigAutoField"
+
+At that time, the default value of :setting:`DEFAULT_AUTO_FIELD` remained
+:class:`django.db.models.AutoField` for backwards compatibility.
+
+In Django 6.0, :setting:`DEFAULT_AUTO_FIELD` now defaults to
+:class:`django.db.models.BigAutoField` and the aforementioned lines in the
+project and app templates are removed.
+
+Most projects shouldn't be affected since there has been a system check warning
+since Django 3.2 if a project doesn't set :setting:`DEFAULT_AUTO_FIELD`:
+
+    **models.W042**: Auto-created primary key used when not defining a primary
+    key type, by default ``django.db.models.AutoField``.
+
+If you haven't dealt with this warning by now, add
+``DEFAULT_AUTO_FIELD = 'django.db.models.AutoField'`` to your project's
+settings, or ``default_auto_field = 'django.db.models.AutoField'`` to an app's
+``AppConfig``, as needed.
+
 Custom ORM expressions should return params as a tuple
 ------------------------------------------------------