Fixed #30253 -- Doc'd how to order nulls in QuerySet.order_by().

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Paul Wayper 2019-03-14 14:08:02 +11:00 committed by Tim Graham
parent 386d89ab55
commit 1025e76429
1 changed files with 5 additions and 1 deletions

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@ -312,10 +312,14 @@ identical to::
Entry.objects.order_by('blog__name')
You can also order by :doc:`query expressions </ref/models/expressions>` by
calling ``asc()`` or ``desc()`` on the expression::
calling :meth:`~.Expression.asc` or :meth:`~.Expression.desc` on the
expression::
Entry.objects.order_by(Coalesce('summary', 'headline').desc())
:meth:`~.Expression.asc` and :meth:`~.Expression.desc` have arguments
(``nulls_first`` and ``nulls_last``) that control how null values are sorted.
Be cautious when ordering by fields in related models if you are also using
:meth:`distinct()`. See the note in :meth:`distinct` for an explanation of how
related model ordering can change the expected results.