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

git-svn-id: http://code.djangoproject.com/svn/django/trunk@13254 bcc190cf-cafb-0310-a4f2-bffc1f526a37
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Russell Keith-Magee 2010-05-14 01:51:14 +00:00
parent 670baf2e48
commit a193f355a8
1 changed files with 7 additions and 6 deletions
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13
docs/topics/db/queries.txt
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@ -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'))