#34597: Queryset (split) exclude's usage of Exists is significantly slower than
subquery
-------------------------------------+-------------------------------------
Reporter: Lorand Varga | Owner: nobody
Type: | Status: new
Cleanup/optimization |
Component: Database layer | Version: 3.2
(models, ORM) |
Severity: Normal | Resolution:
Keywords: | Triage Stage:
| Unreviewed
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
Comment (by Simon Charette):
[https://github.com/django/django/pull/16906 I drafted a PR for the
harmful constant expression comparison] in the mean time and I'll see if
there is a way to do saner `NULL` handling so no `LEFT JOIN` for the sole
purpose of doing an `IS NULL` is necessary. I think it's optimizable when
detecting a `filter_rhs is None`.
--
Ticket URL: <https://code.djangoproject.com/ticket/34597#comment:11>
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/01070188700829f9-95c49c11-7384-4dd2-bfab-f1e091118b1f-000000%40eu-central-1.amazonses.com.
