#36431: values() query on ForeignObject discards additional columns
-------------------------------------+-------------------------------------
Reporter: Jacob Walls | Type: Bug
Status: new | Component: Database
| layer (models, ORM)
Version: 4.2 | Severity: Normal
Keywords: composite primary | Triage Stage:
key | Unreviewed
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
For a multi-column field using `ForeignObject` as modeled
[https://docs.djangoproject.com/en/5.2/topics/composite-primary-key
/#composite-primary-keys-and-relations here], `.values("user")` will
discard columns after the first, and `values("user", "integer")` will
select the second column of `user` into the `integer` namespace.
Here's a failing test for tests/composite_pk/test_values.py:
{{{#!py
def test_foreign_object_values(self):
Comment.objects.create(id=1, user=self.user_1, integer=42)
values = list(Comment.objects.values("user", "integer"))
self.assertEqual(values[0]["integer"], 42)
}}}
{{{
======================================================================
FAIL: test_foreign_object_values
(composite_pk.test_values.CompositePKValuesTests.test_foreign_object_values)
----------------------------------------------------------------------
Traceback (most recent call last):
File "/Users/.../django/tests/composite_pk/test_values.py", line 217, in
test_foreign_object_values
self.assertEqual(values[0]["integer"], 42)
~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^
AssertionError: 1 != 42
}}}
And a similar rough test for foreign_objects/tests.py that fails on Django
4.2, to remove the composite primary key from discussion. (If this model
had more fields, this values query would be more realistic):
{{{#!py
class ForeignObjectValues(TestCase):
def test_foreign_object_values(self):
from .models import Customer
customer_1 = Customer.objects.create(customer_id=1, company="a")
customer_2 = Customer.objects.create(customer_id=1, company="b")
company_a_customers =
Customer.objects.filter(company="a").values("address", "company")
self.assertSequenceEqual(
Customer.objects.exclude(company__in=[cust["company"] for cust
in company_a_customers]),
[customer_2], # Fails, all companies included
)
}}}
--
Ticket URL: <https://code.djangoproject.com/ticket/36431>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.
--
You received this message because you are subscribed to the Google Groups
"Django updates" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To view this discussion visit
https://groups.google.com/d/msgid/django-updates/0107019735ce4c80-86bb4ff7-ac71-4fe6-955f-8ce788623e3b-000000%40eu-central-1.amazonses.com.
