# Updated to 5, now getting "\<object\> matching query does not exist" on my unmanaged model

**URL:** <https://forum.djangoproject.com/t/updated-to-5-now-getting-object-matching-query-does-not-exist-on-my-unmanaged-model/41066>\
**Category:** Mystery Errors\
**Created:** [May 23, 2025, 7:46pm UTC](https://forum.djangoproject.com/t/updated-to-5-now-getting-object-matching-query-does-not-exist-on-my-unmanaged-model/41066 "2025-05-23T19:46:26Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![sagargp](https://sea2.discourse-cdn.com/flex026/user_avatar/forum.djangoproject.com/sagargp/32/28622_2.png) [@sagargp](https://forum.djangoproject.com/u/sagargp)\
**Post date:** [May 23, 2025, 7:46pm UTC](https://forum.djangoproject.com/t/updated-to-5-now-getting-object-matching-query-does-not-exist-on-my-unmanaged-model/41066/1 "2025-05-23T19:46:26Z")

</div>

I’m using Django to make testing easier to read in my non-Django project. The schema is created and managed by me, and I’m writing my own migrations using a homebrew migration tool. To make this work, my models are all declared as unmanaged. Here’s an example:

```sql
create table if not exists bar (
    id bigserial primary key,
    internal_type text
);

create table if not exists foo (
    id bigserial primary key,
    bar bigint references bar(id)
);

```

```python
class Bar(models.Model):
    internal_type = models.TextField()

    class Meta:
        managed = False
        db_table = 'bar'

class Foo(models.Model):
    bar = models.ForeignKey('Bar', models.CASCADE, db_column='bar')

    class Meta:
        managed = False
        db_table = 'foo'

```

```python
def test_foo_bar(self):
    from django_app import models

    self.cursor.execute("INSERT INTO bar(internal_type) VALUES ('test') RETURNING id;")
    self.cursor.execute("INSERT INTO foo(bar) VALUES (%s)", (self.cursor.fetchone()[0],))
    self.cursor.connection.commit()

    a = models.Foo.objects.all()
    b = models.Bar.objects.all()

    assert a[0].bar_id == b[0].id # this succeeds
    
    print(a[0].bar) # this raises an ObjectDoesNotExist error

```

This worked just fine in Django 3.2 and 4.2, but breaks in 5+. It _does_ work if I change `a` to

```python
...
a = mdoels.Foo.objects.all().select_related('bar')
...

```

I dug through the Django release notes, and I didn’t see anything about changes to how related models are loaded. Why is this happening? Is there something I can do to patch over this code-wide? I have hundreds of tests and going through each one to appropriately `select_related` would be prohibitively time consuming.

I did try creating a special model base class that overloads the `get_queryset()` to always `select_related` on foreign key fields, but that doesn’t seem to work for chains of queries, eg, `foo.bar.other_fk.other_field`.

In any case, I’d like to understand what’s going on here a little better.

Some relevant details:

- Postgres 17
- Python 3.11
- Django 5 (also tested on 5.2 – works fine \< 5.0)
- NOT using Django unit tests, these are standard issue `unittests.Testcase` classes (with some magic to load Django in `setUpClass`)
- Using `psycopg2` with my unit tests, and I’ve uninstalled `psycopg` so that Django is also using `psycopg2`
- That this _does_ work as-is on Django \< 5. I could pin our version at 4.2 for now, but I’d rather get all the way up to date. I’m migrating all the way from 3.2.

Edit: It’s probably notable that my traceback includes this:

```python
Traceback (most recent call last):
  File "/usr/local/lib/python3.11/dist-packages/django/db/models/fields/related_descriptors.py", line 235, in __get__
    rel_obj = self.field.get_cached_value(instance)
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/dist-packages/django/db/models/fields/mixins.py", line 15, in get_cached_value
    return instance._state.fields_cache[cache_name]
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^^^^^^^^^^^^
KeyError: 'bar'

```

So it seems like Django thinks this object should be cached, but isn’t?

---

<div class="post-metadata">

**Author:** ![adriagm13](https://sea2.discourse-cdn.com/flex026/user_avatar/forum.djangoproject.com/adriagm13/32/29824_2.png) [@adriagm13](https://forum.djangoproject.com/u/adriagm13)\
**Post date:** [September 10, 2025, 12:08pm UTC](https://forum.djangoproject.com/t/updated-to-5-now-getting-object-matching-query-does-not-exist-on-my-unmanaged-model/41066/2 "2025-09-10T12:08:12Z")

</div>

Has the exact same problem. In our Postgres database the id was big int, but the configuration of DJango for AutoField was:

`DEFAULT_AUTO_FIELD = 'django.db.models.AutoField'`

So just add to the model the field:

```python
class YourModel(models.Model):
    id = models.BigAutoField(primary_key=True)

```

This was the error in our case, not in general.