77 lines
2.9 KiB
ReStructuredText
77 lines
2.9 KiB
ReStructuredText
Release Notes, Usage, Code
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--------------------------
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* Please see `here for release notes, news and discussion`_ (Google Group)
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* Installation and usage: `Documentation and Examples`_ (or the short `Overview`_)
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* The code is on GitHub_ and Bitbucket_ and can also be downloaded as TGZ_ or ZIP_
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.. _here for release notes, news and discussion: http://groups.google.de/group/django-polymorphic/topics
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.. _Documentation and Examples: http://bserve.webhop.org/wiki/django_polymorphic/doc
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.. _GitHub: http://github.com/bconstantin/django_polymorphic
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.. _Bitbucket: http://bitbucket.org/bconstantin/django_polymorphic
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.. _TGZ: http://github.com/bconstantin/django_polymorphic/tarball/master
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.. _ZIP: http://github.com/bconstantin/django_polymorphic/zipball/master
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.. _Overview: http://bserve.webhop.org/wiki/django_polymorphic
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What is django_polymorphic good for?
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------------------------------------
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It implements seamless polymorphic inheritance for Django models.
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This means: objects being retrieved from the database are always returned
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back with the same type/class and fields they were created and saved with.
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An example:
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If we defined the model ``Project`` as a base class for our models
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``ArtProject`` and ``ResearchProject``, and we have stored one of
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each into the database, then we can do::
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>>> Project.objects.all()
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.
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[ <Project: id 1, topic: "John's Gathering">,
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<ArtProject: id 2, topic: "Sculpting with Tim", artist: "T. Turner">,
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<ResearchProject: id 3, topic: "Swallow Aerodynamics", supervisor: "Dr. Winter"> ]
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It doesn't matter how these objects are retrieved: be it through the
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model's own managers/querysets, ForeignKeys, ManyToManyFields
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or OneToOneFields.
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As seen in this example, the resulting querysets are polymorphic,
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and will typically deliver objects of several different types in
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a single query result.
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django_polymorphic does this only for models that explicitely enable it
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(and for their submodels).
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Please see the `Documentation and Examples`_ for more information
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(also included as the file ``DOCS.rst`` with the source).
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Status
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------
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It's important to consider that this code is very new and
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to some extent still experimental. Please see the docs for
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current restrictions, caveats, and performance implications.
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It does seem to work very well for a number of people, but
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API changes, code reorganisations or further schema changes
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are still a possibility. There may also remain larger bugs
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and problems in the code that have not yet been found.
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License
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-------
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django_polymorphic uses the same license as Django (BSD-like).
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Database Schema Change on January 26
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------------------------------------
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| The update from January 26 changed the database schema (more info in the commit-log_).
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| Sorry for any inconvenience. But this should be the final DB schema now.
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.. _commit-log: http://github.com/bconstantin/django_polymorphic/commit/c2b420aea06637966a208329ef7ec853889fa4c7
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