[Django] #32995: Incorrect GROUP BY in ORM query with Function

14 views
Skip to first unread message

Django

unread,
Aug 6, 2021, 9:05:10 AM8/6/21
to django-...@googlegroups.com
#32995: Incorrect GROUP BY in ORM query with Function
-------------------------------------+-------------------------------------
Reporter: Joshua | Owner: nobody
"jag" Ginsberg |
Type: | Status: new
Uncategorized |
Component: Database | Version: 3.1
layer (models, ORM) |
Severity: Normal | Keywords:
Triage Stage: | Has patch: 0
Unreviewed |
Needs documentation: 0 | Needs tests: 0
Patch needs improvement: 0 | Easy pickings: 0
UI/UX: 0 |
-------------------------------------+-------------------------------------
With this model (abbreviated to relevant fields):

{{{
class ListeningLineCall(models.Model):
class CallResult(models.IntegerChoices):
IN_PROGRESS = 1, "In progress"
CONNECTED = 2, "Connected"
LOST = 3, "Lost before connection"
BLOCKED = 4, "Blocked"
UNAVAILABLE = 5, "Unavailable"

class Medium(models.IntegerChoices):
VOICE = 1, "Voice"
SMS = 2, "Text"

caller = models.ForeignKey(ListeningLineCaller,
on_delete=models.CASCADE)
medium = models.PositiveIntegerField(choices=Medium.choices,
default=Medium.VOICE)
call_sid = models.CharField(max_length=34, unique=True, blank=True,
null=True)
result = models.PositiveIntegerField(choices=CallResult.choices,
default=CallResult.IN_PROGRESS)
called_at = models.DateTimeField(auto_now_add=True)
}}}

and the following QuerySet:

{{{
calls_by_date_medium_and_status = (
ListeningLineCall.objects.annotate(called_at_date=TruncDate("called_at")).filter(called_at_date__gt=seven_days_ago,
called_at_date__lt=today)
.exclude(result=ListeningLineCall.CallResult.IN_PROGRESS)
.values_list("medium", "result", "called_at_date")
.annotate(count=Count("call_sid"))
)
}}}

... the following SQL is generated:

{{{
>>> print(calls_by_date_medium_and_status.query)
SELECT "listeningline_listeninglinecall"."medium",
"listeningline_listeninglinecall"."result",
("listeningline_listeninglinecall"."called_at" AT TIME ZONE
'US/Eastern')::date AS "called_at_date",
COUNT("listeningline_listeninglinecall"."call_sid") AS "count" FROM
"listeningline_listeninglinecall" WHERE
(("listeningline_listeninglinecall"."called_at" AT TIME ZONE
'US/Eastern')::date > 2021-07-29 AND
("listeningline_listeninglinecall"."called_at" AT TIME ZONE
'US/Eastern')::date < 2021-08-05 AND NOT
("listeningline_listeninglinecall"."result" = 1)) GROUP BY
"listeningline_listeninglinecall"."medium",
"listeningline_listeninglinecall"."result",
("listeningline_listeninglinecall"."called_at" AT TIME ZONE
'US/Eastern')::date, "listeningline_listeninglinecall"."called_at"
}}}

I expected that the GROUP BY clause would contain the date-truncated
version of `called_at` but I did not expect that it would include the non-
truncated version of `called_at`, the inclusion of which is making my
result-set unusable.

I do not see `called_at` without the function in the Query object's
`group_by` attribute:

{{{
>>> pprint.pprint(calls_by_date_medium_and_status.query.group_by)
(Col(listeningline_listeninglinecall,
listeningline.ListeningLineCall.medium),
Col(listeningline_listeninglinecall,
listeningline.ListeningLineCall.result),
TruncDate(Col(listeningline_listeninglinecall,
listeningline.ListeningLineCall.called_at)))
}}}

--
Ticket URL: <https://code.djangoproject.com/ticket/32995>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.

Django

unread,
Aug 6, 2021, 2:54:09 PM8/6/21
to django-...@googlegroups.com
#32995: Incorrect GROUP BY in ORM query with Function
-------------------------------------+-------------------------------------
Reporter: Joshua "jag" | Owner: nobody
Ginsberg |
Type: Bug | Status: closed
Component: Database layer | Version: 3.1
(models, ORM) |
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 Mariusz Felisiak):

* status: new => closed
* type: Uncategorized => Bug
* resolution: => needsinfo


Comment:

Thanks for the report, unfortunately I cannot reproduce your issue with
provided models and querysets (at least on Django 3.1, 3.2, and the
current `main` branch). Can you provide a sample project?

--
Ticket URL: <https://code.djangoproject.com/ticket/32995#comment:1>

Django

unread,
Aug 7, 2021, 8:21:46 PM8/7/21
to django-...@googlegroups.com
#32995: Incorrect GROUP BY in ORM query with Function
-------------------------------------+-------------------------------------
Reporter: Joshua "jag" | Owner: nobody
Ginsberg |
Type: Bug | Status: new

Component: Database layer | Version: 3.1
(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
-------------------------------------+-------------------------------------
Changes (by Joshua "jag" Ginsberg):

* status: closed => new
* resolution: needsinfo =>


Comment:

I think I found the issue/discrepancy between the model snippet and my
actual one: the default ordering for queries included `called_at` -- which
seems to have affected the GROUP BY, even though `called_at` wasn't in the
query and the resulting SQL didn't have an ORDER BY clause.

This feels like a bug, though not the one I originally believed. Thoughts?

--
Ticket URL: <https://code.djangoproject.com/ticket/32995#comment:2>

Django

unread,
Aug 9, 2021, 12:12:27 AM8/9/21
to django-...@googlegroups.com
#32995: Incorrect GROUP BY in ORM query with Function
-------------------------------------+-------------------------------------
Reporter: Joshua "jag" | Owner: nobody
Ginsberg |
Type: Bug | Status: closed

Component: Database layer | Version: 3.1
(models, ORM) |
Severity: Normal | Resolution: duplicate
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 Mariusz Felisiak):

* status: new => closed

* resolution: => duplicate


Comment:

Thanks for extra details.

> This feels like a bug, though not the one I originally believed.
Thoughts?

It's a duplicate of #32546 (fixed in Django 4.0).

--
Ticket URL: <https://code.djangoproject.com/ticket/32995#comment:3>

Reply all
Reply to author
Forward
0 new messages