django-polymorphic/docs/index.rst
2026-01-13 09:51:16 -08:00

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django-polymorphic
==================
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:pypi:`django-polymorphic` builds on top of the standard Django model inheritance.
It makes using inherited models easier. When a query is made at the base model,
the inherited model classes are returned.
When we store models that inherit from a ``Project`` model...
.. code-block:: python
>>> Project.objects.create(topic="Department Party")
>>> ArtProject.objects.create(topic="Painting with Tim", artist="T. Turner")
>>> ResearchProject.objects.create(topic="Swallow Aerodynamics", supervisor="Dr. Winter")
...and want to retrieve all our projects, the subclassed models are returned!
.. code-block:: python
>>> Project.objects.all()
[ <Project: id 1, topic "Department Party">,
<ArtProject: id 2, topic "Painting with Tim", artist "T. Turner">,
<ResearchProject: id 3, topic "Swallow Aerodynamics", supervisor "Dr. Winter"> ]
Using vanilla Django, we get the base class objects, which is rarely what we wanted:
.. code-block:: python
>>> Project.objects.all()
[ <Project: id 1, topic "Department Party">,
<Project: id 2, topic "Painting with Tim">,
<Project: id 3, topic "Swallow Aerodynamics"> ]
Features
--------
* Full admin integration.
* ORM integration:
- Support for ForeignKey, ManyToManyField, OneToOneField descriptors.
- Support for proxy models.
- Filtering/ordering of inherited models (``ArtProject___artist``).
- Filtering model types: :meth:`~polymorphic.managers.PolymorphicQuerySet.instance_of` and
:meth:`~polymorphic.managers.PolymorphicQuerySet.not_instance_of`
- Combining querysets of different models (``qs3 = qs1 | qs2``)
- Support for custom user-defined managers.
* Formset support.
* Uses the minimum amount of queries needed to fetch the inherited models.
* Disabling polymorphic behavior when needed.
Getting started
---------------
.. toctree::
:maxdepth: 2
quickstart
admin
performance
integrations/index
Advanced topics
---------------
.. toctree::
:maxdepth: 2
formsets
views
migrating
managers
deletion
advanced
changelog/index
api/index
Indices and tables
==================
* :ref:`genindex`
* :ref:`modindex`
* :ref:`search`