Commit f0774927 authored by Russell Keith-Magee's avatar Russell Keith-Magee
Browse files

[1.1.X] Fixed #13532 -- Corrected and clarified examples in F() docs. Thanks... 

[1.1.X] Fixed #13532 -- Corrected and clarified examples in F() docs. Thanks to erw for the report and patch.

Backport of r13254 from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.1.X@13255 bcc190cf-cafb-0310-a4f2-bffc1f526a37
parent c179bd5c

docs/topics/db/queries.txt

+7 −6
Original line number Diff line number Diff line
@@ -512,17 +512,18 @@ than pingbacks, we construct an ``F()`` object to reference the comment count, 
and use that ``F()`` object in the query::



    >>> from django.db.models import F

    >>> Entry.objects.filter(n_pingbacks__lt=F('n_comments'))

    >>> Entry.objects.filter(n_comments__gt=F('n_pingbacks'))



Django supports the use of addition, subtraction, multiplication,

division and modulo arithmetic with ``F()`` objects, both with constants

and with other ``F()`` objects. To find all the blog entries with *twice* as

many comments as pingbacks, we modify the query::

and with other ``F()`` objects. To find all the blog entries with more than

*twice* as many comments as pingbacks, we modify the query::



    >>> Entry.objects.filter(n_pingbacks__lt=F('n_comments') * 2)

    >>> Entry.objects.filter(n_comments__gt=F('n_pingbacks') * 2)



To find all the entries where the sum of the pingback count and comment count

is greater than the rating of the entry, we would issue the query::

To find all the entries where the rating of the entry is less than the

sum of the pingback count and comment count, we would issue the

query::



    >>> Entry.objects.filter(rating__lt=F('n_comments') + F('n_pingbacks'))