#31573: QuerySet.update().order_by() not working as expected on MySQL
-------------------------------------+-------------------------------------
Reporter: Gerben | Owner: nobody
Morsink |
Type: Bug | Status: new
Component: Database | Version: 2.2
layer (models, ORM) |
Severity: Normal | Keywords: queryset update
Triage Stage: | Has patch: 0
Unreviewed |
Needs documentation: 0 | Needs tests: 0
Patch needs improvement: 0 | Easy pickings: 0
UI/UX: 0 |
-------------------------------------+-------------------------------------
When a UniqueConstraint is used on an IntegerField and we want to update
multiple rows of that field at once, we need to make sure we select the
right order before the update, since MySQL does not support a deferred
update (see: https://dev.mysql.com/doc/refman/5.7/en/update.html).
I expected simply doing:
qs.order_by('-integerfield').update(integerfield=F('integerfield')+1)
would work, but it seems the Django ORM strips the order_by from the query
before execution, it gives a django.db.utils.IntegrityError: (1062,
"Duplicate entry '' for key 'integerfield'").
--
Ticket URL: <https://code.djangoproject.com/ticket/31573>
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 on the web visit
https://groups.google.com/d/msgid/django-updates/049.b05b8553486270e2bce96a4c2421ea08%40djangoproject.com.
