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Simplified example in 'Limiting QuerySets' section of docs/db-api.txt. 

git-svn-id: http://code.djangoproject.com/svn/django/trunk@2855 bcc190cf-cafb-0310-a4f2-bffc1f526a37
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Adrian Holovaty 2006-05-06 03:44:14 +00:00
parent 4bc4aa2fa6
commit 862328a98f
1 changed files with 11 additions and 4 deletions
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docs/db-api.txt
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@ -335,11 +335,18 @@ return a list of every *second* object of the first 10::
Entry.objects.all()[:10:2] Entry.objects.all()[:10:2]
To retrieve a *single* object rather than a list To retrieve a *single* object rather than a list
(e.g. ``SELECT foo FROM bar LIMIT 1``), slice the ``QuerySet`` to ``[:1]`` and (e.g. ``SELECT foo FROM bar LIMIT 1``), using a simple index instead of a
call ``get()`` on that. For example, this returns the first ``Entry`` in the slice. For example, this returns the first ``Entry`` in the database, after
database, after ordering entries alphabetically by headline:: ordering entries alphabetically by headline::
Entry.objects.order_by('headline')[:1].get() Entry.objects.order_by('headline')[0]
This is equivalent to::
Entry.objects.order_by('headline')[0:1].get()
Note that either of these two examples will raise ``DoesNotExist`` if no
objects match the given criteria.
QuerySet methods that return new QuerySets QuerySet methods that return new QuerySets
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