Fixed #14599 -- Added documentation for QuerySet.delete() in the QuerySet API reference. Thanks to abeld for the report.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@14505 bcc190cf-cafb-0310-a4f2-bffc1f526a37
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Carl Meyer 2010-11-09 16:33:48 +00:00
parent 60ad315bc9
commit 3ba3294c6b
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@ -1246,6 +1246,37 @@ The ``update()`` method does a bulk update and does not call any ``save()``
methods on your models, nor does it emit the ``pre_save`` or ``post_save`` methods on your models, nor does it emit the ``pre_save`` or ``post_save``
signals (which are a consequence of calling ``save()``). signals (which are a consequence of calling ``save()``).
``delete()``
~~~~~~~~~~~~~~~~~~~~
.. method:: delete()
Performs an SQL delete query on all rows in the :class:`QuerySet`. The
``delete()`` is applied instantly. You cannot call ``delete()`` on a
:class:`QuerySet` that has had a slice taken or can otherwise no longer be
filtered.
For example, to delete all the entries in a particular blog::
>>> b = Blog.objects.get(pk=1)
# Delete all the entries belonging to this Blog.
>>> Entry.objects.filter(blog=b).delete()
Django emulates the SQL constraint ``ON DELETE CASCADE`` -- in other words, any
objects with foreign keys pointing at the objects to be deleted will be deleted
along with them. For example::
blogs = Blog.objects.all()
# This will delete all Blogs and all of their Entry objects.
blogs.delete()
The ``delete()`` method does a bulk delete and does not call any ``delete()``
methods on your models. It does, however, emit the
:data:`~django.db.models.signals.pre_delete` and
:data:`~django.db.models.signals.post_delete` signals for all deleted objects
(including cascaded deletions).
.. _field-lookups: .. _field-lookups:
Field lookups Field lookups