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Fixed #13263 -- Corrected field name typo in queries documentation examples. Thanks, RicherPots for bug report and gabrielhurley for the patch. 

git-svn-id: http://code.djangoproject.com/svn/django/trunk@12926 bcc190cf-cafb-0310-a4f2-bffc1f526a37
This commit is contained in:
Justin Bronn 2010-04-05 15:57:00 +00:00
parent 7cc4046802
commit e07570f10e
1 changed files with 5 additions and 5 deletions
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10
docs/topics/db/queries.txt
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@ -419,7 +419,7 @@ models doesn't have a value that meets the filter condition, Django will treat
it as if there is an empty (all values are ``NULL``), but valid, object there.
All this means is that no error will be raised. For example, in this filter::
Blog.objects.filter(entry__author__name='Lennon')
Blog.objects.filter(entry__authors__name='Lennon')
(if there was a related ``Author`` model), if there was no ``author``
associated with an entry, it would be treated as if there was also no ``name``
@ -427,14 +427,14 @@ attached, rather than raising an error because of the missing ``author``.
Usually this is exactly what you want to have happen. The only case where it
might be confusing is if you are using ``isnull``. Thus::
Blog.objects.filter(entry__author__name__isnull=True)
Blog.objects.filter(entry__authors__name__isnull=True)
will return ``Blog`` objects that have an empty ``name`` on the ``author`` and
also those which have an empty ``author`` on the ``entry``. If you don't want
those latter objects, you could write::
Blog.objects.filter(entry__author__isnull=False,
entry__author__name__isnull=True)
Blog.objects.filter(entry__authors__isnull=False,
entry__authors__name__isnull=True)
Spanning multi-valued relationships
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@ -532,7 +532,7 @@ any joins needed to access the related object. For example, to retrieve all
the entries where the author's name is the same as the blog name, we could
issue the query:
>>> Entry.objects.filter(author__name=F('blog__name'))
>>> Entry.objects.filter(authors__name=F('blog__name'))
The pk lookup shortcut
----------------------