[Django] #26777: Cannot add foreign key constraint when migrating manytomany field
Django
-------------------------------+--------------------
Reporter: Uninen | Owner: nobody
Type: Uncategorized | Status: new
Component: Migrations | Version: 1.9
Severity: Normal | Keywords:
Triage Stage: Unreviewed | Has patch: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------+--------------------
I have a model that looks like
{{{
class LiveEvent(models.Model):
id = models.UUIDField(primary_key=True, default=uuid.uuid4,
editable=False)
...
attendees = models.ManyToManyField(User, blank=True,
related_name="events_attended")
...
notify_subscriptions = models.ManyToManyField(User, blank=True,
related_name="events_subscribed")
}}}
when trying to add and migrate notify_subscriptions field I get an
`django.db.utils.IntegrityError: (1215, 'Cannot add foreign key
constraint')` error. When adding
{{{
'OPTIONS': {
"init_command": "SET foreign_key_checks = 0;",
},
}}}
to database settings , the error becames:
`django.db.utils.OperationalError: (1825, "Failed to add the foreign key
constraint on table 'levan_liveevent_notify_subscriptions'. Incorrect
options in FOREIGN KEY constraint
'slipmat/levan_liveevent_noti_liveevent_id_a4871abc_fk_levan_liveevent_id'")`
the migration file looks like:
{{{
operations = [
migrations.AddField(
model_name='liveevent',
name='notify_subscriptions',
field=models.ManyToManyField(blank=True,
related_name='events_subscribed', to=settings.AUTH_USER_MODEL),
),
]
}}}
I'm using MySQL version 5.6.27 and Django version 1.9.7
--
Ticket URL: <https://code.djangoproject.com/ticket/26777>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.
Django
Reporter: Uninen | Owner: nobody
Type: Bug | Status: closed
Component: Migrations | Version: 1.9
Severity: Normal | Resolution: needsinfo
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 charettes):
* status: new => closed
* needs_better_patch: => 0
* needs_tests: => 0
* type: Uncategorized => Bug
* needs_docs: => 0
* resolution: => needsinfo
Old description:
New description:
I have a model that looks like
{{{#!python
class LiveEvent(models.Model):
id = models.UUIDField(primary_key=True, default=uuid.uuid4,
editable=False)
...
attendees = models.ManyToManyField(
User, blank=True, related_name="events_attended"
)
...
notify_subscriptions = models.ManyToManyField(
User, blank=True, related_name="events_subscribed"
)
}}}
when trying to add and migrate notify_subscriptions field I get the
following error:
{{{
django.db.utils.IntegrityError: (1215, 'Cannot add foreign key
constraint')`
}}}
When adding
{{{#!python
'OPTIONS': {
"init_command": "SET foreign_key_checks = 0;",
},
}}}
to database settings , the error became:
{{{
django.db.utils.OperationalError: (1825, "Failed to add the foreign key
constraint on table 'levan_liveevent_notify_subscriptions'. Incorrect
options in FOREIGN KEY constraint
'slipmat/levan_liveevent_noti_liveevent_id_a4871abc_fk_levan_liveevent_id'")
}}}
the migration file looks like:
{{{#!python
operations = [
migrations.AddField(
model_name='liveevent',
name='notify_subscriptions',
field=models.ManyToManyField(
blank=True, related_name='events_subscribed',
to=settings.AUTH_USER_MODEL
),
),
]
}}}
I'm using MySQL version 5.6.27 and Django version 1.9.7
--
Comment:
I just tried reproducing against Django 1.9.7 with no success.
Please re-open the ticket by answering these two questions:
1. Are both of your tables using the InnoDB engine? Foreign keys are not
supported on MyISAM.
2. Are you using a custom user model which you didn't provide the
definition?
--
Ticket URL: <https://code.djangoproject.com/ticket/26777#comment:1>
Django
Reporter: Uninen | Owner: nobody
Type: Bug | Status: new
Component: Migrations | Version: 1.9
Severity: Normal | Resolution:
Keywords: | Triage Stage: Unreviewed
Has patch: 0 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Changes (by Uninen):
* status: closed => new
* resolution: needsinfo =>
Comment:
1. Yes, both tables are using InnoDB engine.
2. No, I'm not using a custom user model
--
Ticket URL: <https://code.djangoproject.com/ticket/26777#comment:2>
Django
Reporter: Uninen | Owner: nobody
Type: Bug | Status: new
Component: Migrations | Version: 1.9
Severity: Normal | Resolution:
Keywords: | Triage Stage: Unreviewed
Has patch: 0 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Comment (by Uninen):
FWIW, adding `db_constraint=False` to the `notify_subscriptions` field
produces a migration that runs flawlessly. That's my workaround for now.
--
Ticket URL: <https://code.djangoproject.com/ticket/26777#comment:3>
Django
Reporter: Uninen | Owner: nobody
Type: Bug | Status: new
Component: Migrations | Version: 1.9
Severity: Normal | Resolution:
Keywords: | Triage Stage: Unreviewed
Has patch: 0 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Comment (by charettes):
Are you using Oracle's MySQL backend or `django.db.backends.mysql`?
--
Ticket URL: <https://code.djangoproject.com/ticket/26777#comment:4>
Django
Reporter: Uninen | Owner: nobody
Type: Bug | Status: closed
Component: Migrations | Version: 1.9
Severity: Normal | Resolution: invalid
Keywords: | Triage Stage: Unreviewed
Has patch: 0 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Changes (by charettes):
* cc: charettes (added)
* status: new => closed
* resolution: => invalid
Comment:
Please inspect your database and provide us with the datatype of both
`LiveEvent`'s table `id` column and the intermediary table's
(`notify_subscriptions`) column referencing the former.
--
Ticket URL: <https://code.djangoproject.com/ticket/26777#comment:5>