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Fixed #17528 -- Documented that add() and remove() with a many-to-many relationship do not call Model.save()
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@ -48,6 +48,14 @@ Related objects reference
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>>> e = Entry.objects.get(id=234)
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>>> b.entry_set.add(e) # Associates Entry e with Blog b.
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In the example above, ``e.save()`` is called to perform the update.
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Using ``add()`` with a many-to-many relationship, however, will not
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call any ``save()`` methods, but rather create the relationships
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using :meth:`QuerySet.bulk_create()
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<django.db.models.query.QuerySet.bulk_create>`. If you need to execute
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some custom logic when a relationship is created, listen to the
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:data:`~django.db.models.signals.m2m_changed` signal.
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.. method:: create(**kwargs)
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Creates a new object, saves it and puts it in the related object set.
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@ -86,6 +94,14 @@ Related objects reference
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>>> e = Entry.objects.get(id=234)
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>>> b.entry_set.remove(e) # Disassociates Entry e from Blog b.
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Similar to :meth:`add()`, ``e.save()`` is called in the example above
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to perform the update. Using ``remove()`` with a many-to-many
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relationship, however, will delete the relationships using
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:meth:`QuerySet.delete()<django.db.models.query.QuerySet.delete>` which
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means no model ``save()`` methods are called; listen to the
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:data:`~django.db.models.signals.m2m_changed` signal if you wish to
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execute custom code when a relationship is deleted.
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For :class:`~django.db.models.ForeignKey` objects, this method only
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exists if ``null=True``. If the related field can't be set to ``None``
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(``NULL``), then an object can't be removed from a relation without
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