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
12240	select_related doesn't work correctly when mixing nullable and non-nullable keys	Michał Bartoszkiewicz	nobody	"The following models:
{{{
class Model1(models.Model):
    x = models.ForeignKey('Model2', null=True)

class Model2(models.Model):
    y = models.ForeignKey('Model3', null=False)

class Model3(models.Model):
    z = models.ForeignKey('Model4', null=False)

class Model4(models.Model):
    q = models.IntegerField()
}}}
cause a problem with select_related():
{{{
In [4]: models.Model1.objects.select_related('x__y')
Out[4]: [<Model1: Model1 object>]

In [5]: models.Model1.objects.select_related('x__y__z')
Out[5]: []
}}}

It look like the fix for #7369 only fixed a case when a single non-nullable ForeignKey is encountered, not when there are two in a row."		closed	Database layer (models, ORM)	1.1		fixed			Ready for checkin	1	0	0	0	0	0