[1.2.X] Some small fixes to DB optimization docs.

Backport of [15122] from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.2.X@15123 bcc190cf-cafb-0310-a4f2-bffc1f526a37
This commit is contained in:
Luke Plant 2010-12-31 15:48:51 +00:00
parent 2d854539c3
commit fa4ac6f80c
1 changed files with 3 additions and 2 deletions

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@ -191,7 +191,7 @@ Don't overuse ``count()`` and ``exists()``
If you are going to need other data from the QuerySet, just evaluate it.
For example, assuming an Email class that has a ``body`` attribute and a
For example, assuming an Email model that has a ``body`` attribute and a
many-to-many relation to User, the following template code is optimal:
.. code-block:: html+django
@ -212,7 +212,8 @@ many-to-many relation to User, the following template code is optimal:
It is optimal because:
1. Since QuerySets are lazy, this does no database if 'display_inbox' is False.
1. Since QuerySets are lazy, this does no database queries if 'display_inbox'
is False.
#. Use of ``with`` means that we store ``user.emails.all`` in a variable for
later use, allowing its cache to be re-used.