Queryset unions are sometimes incorrect.

[Ben]

Queryset unions are in this case incorrect. It appears that an 'inner join' is
not being converted into an 'outer join' when it should be. See the example below.

import unittest
from django.db import models

class ObjectA(models.Model):
    name = models.CharField(max_length=50)

class ObjectB(models.Model):
    name = models.CharField(max_length=50)
    objecta = models.ForeignKey(ObjectA)
    number = models.PositiveSmallIntegerField()

class TestStuff(unittest.TestCase):

    def test_stuff(self):
        names = ['one', 'two', 'three', 'four', 'five', 'six', 'seven']
        obs = [ObjectA(name=name) for name in names]
        for o in obs:
            o.save()
        b_infos = [('fish', 5, obs[0]), ('turtle', 9, obs[0]),
                   ('fish', 6, obs[3])]
        ob_bs = [ObjectB(name=name, objecta=objecta, number=number)
                 for name, number, objecta in b_infos]
        for o in ob_bs:
            o.save()
        all_query = ObjectA.objects.all()
        filter1_query = ObjectA.objects.filter(objectb__name='fish')
        filter2_query = ObjectA.objects.filter(objectb__name='fish',
                                               objectb__number=6)
        # The tests with filter1_query pass for me.
	self.assertEqual(set(all_query | filter1_query),
                         set(all_query) | set(filter1_query))
	self.assertEqual(set(filter1_query | all_query),
                         set(all_query) | set(filter1_query))
        # The second test with filter2_query fails for me.
        self.assertEqual(set(all_query | filter2_query),
                         set(all_query) | set(filter2_query))
        self.assertEqual(set(filter2_query | all_query),
                         set(all_query) | set(filter2_query))

[Ben]

I've uploaded a patch (although it's not displaying properly) which appears to correct this problem, and a regression test to go with it.

[Ben]

second attempt to get the patch to display correctly

[Karen Tracey]

Updated patch to apply cleanly

[Mark Lavin]

I'm seeing a similar issue in my project where queryset OR is not commutative. One way produces a LEFT OUTER JOIN and the other produces an INNER JOIN. This patch resolves this issue for me.

[Karen Tracey]

Near as I can tell, this is good to go, though I'd be happier if someone with more ORM clues than me would give it look...

[Ramiro Morales]

Karen, no enough ORM fu here, but updated the patch removing unneeded code in tests (init(), setUp())

[Russell Keith-Magee]

In [15726]:

Fixed #12252 -- Ensure that queryset unions are commutative. Thanks to benreynwar for the report, and draft patch, and to Karen and Ramiro for the review eyeballs and patch updates.

[Russell Keith-Magee]

In [15727]:

[1.2.X] Fixed #12252 -- Ensure that queryset unions are commutative. Thanks to benreynwar for the report, and draft patch, and to Karen and Ramiro for the review eyeballs and patch updates.

Backport of r15726 from trunk.

[Philippe Raoult]

patch for 1.2.5 in case anyone needs it (fix is commited in 1.2.X branch)

[Jacob]

Milestone 1.3 deleted