docs/topic/index.rst
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Key topics
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Limitations
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Revert and recover
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Be aware that reverting a model instance will also revert all related (i.e. via a foreign key)
object instances to the same history point - this will not always be the desired behaviour, and may
not be what is expected by your site's content editors.
Possible database integrity errors
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If:
* a model has non-nullable foreign keys (``null=False``), *and*
* these foreign keys are not registered using the :ref:`follow` option, *and*
* a reversion action deletes a related object
then you will face a database ``IntegrityError``.
To avoid this, ensure that such foreign keys are registered using the the :ref:`follow` keyword.
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Missing admin options
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If the **Recover deleted** button on a model's changelist admin view seems to be missing,
or you cannot access the *history revert* mechanism, then most likely this model has not
been correctly registered with ``VersionedPlaceholderAdminMixin``. See :ref:`admin_registration`