Re: How to do equivalent of LEFT JOIN ON in Django (returning all Left rows, when Right item may not exist)

On Thu, Oct 06, 2011 at 12:05:09PM -0700, Attempting Django wrote:
> Hi guys, can anyone please give me an example of how to do equivalent
> of a LEFT JOIN ON in Django?? I am trying to return every row from one
> table on the left, with any matches in a foreign table on the right
> (there will be only one or NULL match possible). The issue I'm having
> is showing left table data when there is a NULL on the right. Thanks!
Django does this by default on nullable ForeignKeys. All you need to
do is something like::

MyModel.objects.select_related('foreignkey_field')

Behind the scenes, Django does a JOIN. Its type (INNER od LEFT OUTER)
is decided based on whether the left-hand column (your ForeignKey
field) is allowed to be NULL or not.

Michal