id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
16439	select_related does not work with nullable fields unless field is specified.	Dan Loewenherz	nobody	"Say I have the following model:

  
{{{
class Book(models.Model):
      owner = models.ForeignKey(Owner, related_name='books')
}}}


`Book.objects.select_related()` will pull in all owner data. HOWEVER, when the owner field is nullable, no joins occur.

{{{
class Book(models.Model):
    owner = models.ForeignKey(Owner, null=True, blank=True, related_name='books')
}}}

Running a join in my database involving a nullable field works exactly as would one on a non-nullable field, so I can't really see a good reason for this to happen. 
"	Bug	closed	Documentation	1.3	Normal	fixed	db		Accepted	0	1	0	0	0	0