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-rw-r--r--docs/topics/db/examples/many_to_many.txt5
-rw-r--r--docs/topics/db/models.txt41
2 files changed, 18 insertions, 28 deletions
diff --git a/docs/topics/db/examples/many_to_many.txt b/docs/topics/db/examples/many_to_many.txt
index ed4a093964..746fb2f550 100644
--- a/docs/topics/db/examples/many_to_many.txt
+++ b/docs/topics/db/examples/many_to_many.txt
@@ -34,10 +34,7 @@ objects, and a ``Publication`` has multiple ``Article`` objects:
return self.headline
What follows are examples of operations that can be performed using the Python
-API facilities. Note that if you are using :ref:`an intermediate model
-<intermediary-manytomany>` for a many-to-many relationship, some of the related
-manager's methods are disabled, so some of these examples won't work with such
-models.
+API facilities.
Create a few ``Publications``::
diff --git a/docs/topics/db/models.txt b/docs/topics/db/models.txt
index 1a340a4567..f895db89fa 100644
--- a/docs/topics/db/models.txt
+++ b/docs/topics/db/models.txt
@@ -511,37 +511,31 @@ the intermediate model::
>>> beatles.members.all()
<QuerySet [<Person: Ringo Starr>, <Person: Paul McCartney>]>
-Unlike normal many-to-many fields, you *can't* use ``add()``, ``create()``,
-or ``set()`` to create relationships::
+You can also use ``add()``, ``create()``, or ``set()`` to create relationships,
+as long as your specify ``through_defaults`` for any required fields::
- >>> # The following statements will not work
- >>> beatles.members.add(john)
- >>> beatles.members.create(name="George Harrison")
- >>> beatles.members.set([john, paul, ringo, george])
+ >>> beatles.members.add(john, through_defaults={'date_joined': date(1960, 8, 1)})
+ >>> beatles.members.create(name="George Harrison", through_defaults={'date_joined': date(1960, 8, 1)})
+ >>> beatles.members.set([john, paul, ringo, george], through_defaults={'date_joined': date(1960, 8, 1)})
-Why? You can't just create a relationship between a ``Person`` and a ``Group``
-- you need to specify all the detail for the relationship required by the
-``Membership`` model. The simple ``add``, ``create`` and assignment calls
-don't provide a way to specify this extra detail. As a result, they are
-disabled for many-to-many relationships that use an intermediate model.
-The only way to create this type of relationship is to create instances of the
-intermediate model.
+You may prefer to create instances of the intermediate model directly.
-The :meth:`~django.db.models.fields.related.RelatedManager.remove` method is
-disabled for similar reasons. For example, if the custom through table defined
-by the intermediate model does not enforce uniqueness on the
-``(model1, model2)`` pair, a ``remove()`` call would not provide enough
-information as to which intermediate model instance should be deleted::
+If the custom through table defined by the intermediate model does not enforce
+uniqueness on the ``(model1, model2)`` pair, allowing multiple values, the
+:meth:`~django.db.models.fields.related.RelatedManager.remove` call will
+remove all intermediate model instances::
>>> Membership.objects.create(person=ringo, group=beatles,
... date_joined=date(1968, 9, 4),
... invite_reason="You've been gone for a month and we miss you.")
>>> beatles.members.all()
<QuerySet [<Person: Ringo Starr>, <Person: Paul McCartney>, <Person: Ringo Starr>]>
- >>> # This will not work because it cannot tell which membership to remove
+ >>> # This deletes both of the intermediate model instances for Ringo Starr
>>> beatles.members.remove(ringo)
+ >>> beatles.members.all()
+ <QuerySet [<Person: Paul McCartney>]>
-However, the :meth:`~django.db.models.fields.related.RelatedManager.clear`
+The :meth:`~django.db.models.fields.related.RelatedManager.clear`
method can be used to remove all many-to-many relationships for an instance::
>>> # Beatles have broken up
@@ -550,10 +544,9 @@ method can be used to remove all many-to-many relationships for an instance::
>>> Membership.objects.all()
<QuerySet []>
-Once you have established the many-to-many relationships by creating instances
-of your intermediate model, you can issue queries. Just as with normal
-many-to-many relationships, you can query using the attributes of the
-many-to-many-related model::
+Once you have established the many-to-many relationships, you can issue
+queries. Just as with normal many-to-many relationships, you can query using
+the attributes of the many-to-many-related model::
# Find all the groups with a member whose name starts with 'Paul'
>>> Group.objects.filter(members__name__startswith='Paul')