[Django] #21257: ForeignKey on_delete functionality should traverse (cascade, ha ha) to the DB backend
Django
DB backend
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Reporter: gcbirzan | Owner: nobody
Type: New feature | Status: new
Component: Uncategorized | Version: master
Severity: Normal | Keywords:
Triage Stage: Unreviewed | Has patch: 0
Easy pickings: 0 | UI/UX: 0
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By default, django creates FKs without an explicit ON DELETE on the
backend. This, if nothing else, should be configurable. If for no other
reason that when using some transaction isolation modes, the error
returned by the backend will be the wrong one during concurrent
modifications:
Table b links to table a. You insert in table b a link to ID 1 in a, at
the same time as you delete it from a.
With the default (at least in PostgreSQL), in REPEATABLE READ, the error
is IntegrityError, which is wrong, since in fact you should just retry the
transaction. In lower isolation levels, the FK is deleted (as expected),
though, granted the on delete signals are not called.
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Ticket URL: <https://code.djangoproject.com/ticket/21257>
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Django
DB backend
Reporter: gcbirzan | Owner: nobody
Type: New feature | Status: new
Component: Uncategorized | Version: master
Keywords: | Triage Stage: Unreviewed
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
Changes (by mjtamlyn):
* needs_better_patch: => 0
* needs_tests: => 0
* needs_docs: => 0
Comment:
This is likely related to the mailing list conversation
https://docs.djangoproject.com/en/dev/ref/django-admin/#runserver-port-or-
address-port and the ticket #21127. Basically the consensus seems to be
that if we do push to the database it will be a new option to `on_delete`
in the FK declaration. This is also likely to be bundled with the removal
of a default behaviour for `on_delete`.
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Ticket URL: <https://code.djangoproject.com/ticket/21257#comment:1>
Django
DB backend
Reporter: gcbirzan | Owner: nobody
Type: New feature | Status: new
Component: Uncategorized | Version: master
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Changes (by mjtamlyn):
* stage: Unreviewed => Accepted
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Ticket URL: <https://code.djangoproject.com/ticket/21257#comment:2>
Django
DB backend
Reporter: gcbirzan | Owner: nobody
Type: New feature | Status: new
Component: Uncategorized | Version: master
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Comment (by anonymous):
I think the URL should be https://groups.google.com/forum/#!topic/django-
developers/FJMoGgtYIX4
Anyway, it is, but this doesn't involve any default behaviour change, so
it should be way easier.
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Ticket URL: <https://code.djangoproject.com/ticket/21257#comment:3>
Django
DB backend
Reporter: gcbirzan | Owner: nobody
Type: New feature | Status: new
(models, ORM) | Resolution:
Severity: Normal | Triage Stage: Accepted
Keywords: | Needs documentation: 0
Has patch: 0 | Patch needs improvement: 0
Needs tests: 0 | UI/UX: 0
Easy pickings: 0 |
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Changes (by timo):
* component: Uncategorized => Database layer (models, ORM)
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Ticket URL: <https://code.djangoproject.com/ticket/21257#comment:4>
Django
DB backend
Reporter: gcbirzan | Owner: nobody
Type: New feature | Status: closed
Component: Database layer | Version: master
(models, ORM) |
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Changes (by timgraham):
* status: new => closed
* resolution: => duplicate
Comment:
Duplicate of #21961
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Ticket URL: <https://code.djangoproject.com/ticket/21257#comment:5>