#24692: QuerySet.extra(select=...) is silently dropped with aggregations
-------------------------------------+-------------------------------------
Reporter: jdelic | Owner: nobody
Type: Uncategorized | Status: new
Component: Database layer | Version: 1.8
(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 jdelic):
> Looking at it a bit more, though, I noticed that period doesn't seem to
be used in the values or in the annotate. Do you have a typo there?
No, not a typo per se. Maybe a mistake, though. I'm basing this off the
{{{is_recent}}} example in
https://docs.djangoproject.com/en/1.8/ref/models/querysets/#extra, which
also doesn't mention the field anywhere else. It might be worth mentioning
that if you add {{{.values('service_id', 'period')}}} then the QuerySet
will generate invalid SQL:
{{{
#!python
>>> qs = ServiceAction.objects.extra(select={'period':
'(MAX("dbtest_serviceaction"."performed")-MIN("dbtest_serviceaction"."performed"))'}).values('service_id',
'period').annotate(first_action=Min('performed'),
last_action=Max('performed'))
>>> print(qs.query)
SELECT
((MAX("dbtest_serviceaction"."performed")-MIN("dbtest_serviceaction"."performed")))
AS "period", "dbtest_serviceaction"."service_id",
MAX("dbtest_serviceaction"."performed") AS "last_action",
MIN("dbtest_serviceaction"."performed") AS "first_action" FROM
"dbtest_serviceaction" GROUP BY "dbtest_serviceaction"."service_id",
((MAX("dbtest_serviceaction"."performed")-MIN("dbtest_serviceaction"."performed")))
>>> qs
...
OperationalError: aggregate functions are not allowed in the GROUP BY
clause
}}}
--
Ticket URL: <https://code.djangoproject.com/ticket/24692#comment:7>
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 django-updates+unsubscr...@googlegroups.com.
To post to this group, send email to django-updates@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/django-updates/064.d7e80c38ce0f03681347cf688c7b7e35%40djangoproject.com.
For more options, visit https://groups.google.com/d/optout.
