Opened 3 years ago
Closed 3 years ago
#33512 closed Bug (duplicate)
Creating a child instance with a parent containing DateTimeField(auto_add_now=True) raises IntegrityError.
Reported by: | Eriks K | Owned by: | nobody |
---|---|---|---|
Component: | Database layer (models, ORM) | Version: | 4.0 |
Severity: | Normal | Keywords: | auto_add_now |
Cc: | Triage Stage: | Unreviewed | |
Has patch: | no | Needs documentation: | no |
Needs tests: | no | Patch needs improvement: | no |
Easy pickings: | no | UI/UX: | no |
Description (last modified by )
Description:
When creating Model object which inherits from other Model which has DateTimeField
with auto_add_now=True
and passing parent_ptr_id
value, then Django tries to update base Model by setting the auto_now_add field to NUL (although the field is null=False)
Expected result:
ChildModel instance created with a link to ParentModel.
Code examples:
models.py
class ParentModel(models.Model): created = models.DateTimeField(auto_now_add=True) modified = models.DateTimeField(auto_now=True) class ChildModel(ParentModel): some_field = models.CharField(max_length=12)
manage.py shell
from app.models import ParentModel, ChildModel parent_object = ParentModel.objects.create() # OK ChildModel.objects.create() # OK ChildModel.objects.create(parentmodel_ptr=parent_object) # IntegrityError
Actual result:
Django tries to update ParentModel's created
with NULL
UPDATE "app_parentmodel" SET "created" = NULL, "modified" = ? WHERE "app_parentmodel"."id" = ?
And raises
django.db.utils.IntegrityError: NOT NULL constraint failed: app_parentmodel.created
Noticed in Django 2.2, reproduced in 3.2 and 4.0. with both Postgres and SQlite database backends.
Demo project on GitHub to reproduce bug.
Change History (1)
comment:1 by , 3 years ago
Description: | modified (diff) |
---|---|
Resolution: | → duplicate |
Status: | new → closed |
Summary: | DateTimeField auto_add_now is NUL when creating child model object referencing parent model's object → Creating a child instance with a parent containing DateTimeField(auto_add_now=True) raises IntegrityError. |
Thanks for the report! It looks like a different scenario for the same issue as described in #24539.