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Fixed #10981 -- Clarified documentation regarding lazy cross-applicat…

…ion relationships. Thanks to Ramiro for the suggestion.

git-svn-id: bcc190cf-cafb-0310-a4f2-bffc1f526a37
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freakboy3742 committed Jun 10, 2009
1 parent 74131e8 commit 6c36d4c4f8379433cdce150a64dad6a1f16097cd
Showing with 20 additions and 10 deletions.
  1. +20 −10 docs/ref/models/fields.txt
@@ -800,21 +800,22 @@ you can use the name of the model, rather than the model object itself::
class Manufacturer(models.Model):
# ...
-Note, however, that this only refers to models in the same ```` file --
-you cannot use a string to reference a model defined in another application or
-imported from elsewhere.
-.. versionchanged:: 1.0
- Refering models in other applications must include the application label.
+.. versionadded:: 1.0
-To refer to models defined in another
-application, you must instead explicitly specify the application label. For
-example, if the ``Manufacturer`` model above is defined in another application
-called ``production``, you'd need to use::
+To refer to models defined in another application, you can explicitly specify
+a model with the full application label. For example, if the ``Manufacturer``
+model above is defined in another application called ``production``, you'd
+need to use::
class Car(models.Model):
manufacturer = models.ForeignKey('production.Manufacturer')
+This sort of reference can be useful when resolving circular import
+dependencies between two applications.
+Database Representation
Behind the scenes, Django appends ``"_id"`` to the field name to create its
database column name. In the above example, the database table for the ``Car``
model will have a ``manufacturer_id`` column. (You can change this explicitly by
@@ -824,6 +825,9 @@ deal with the field names of your model object.
.. _foreign-key-arguments:
:class:`ForeignKey` accepts an extra set of arguments -- all optional -- that
define the details of how the relation works.
@@ -871,6 +875,9 @@ the model is related. This works exactly the same as it does for
:class:`ForeignKey`, including all the options regarding :ref:`recursive
<recursive-relationships>` and :ref:`lazy <lazy-relationships>` relationships.
+Database Representation
Behind the scenes, Django creates an intermediary join table to represent the
many-to-many relationship. By default, this table name is generated using the
names of the two tables being joined. Since some databases don't support table
@@ -882,6 +889,9 @@ You can manually provide the name of the join table using the
.. _manytomany-arguments:
:class:`ManyToManyField` accepts an extra set of arguments -- all optional --
that control how the relationship functions.

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