#32478: Queryset annotation mixing aggregate and subquery doesn't GROUP BY outer
column references.
-------------------------------------+-------------------------------------
Reporter: Igor Pejic | Owner: Simon
| Charette
Type: Bug | Status: assigned
Component: Database layer | Version: 3.0
(models, ORM) |
Severity: Normal | Resolution:
Keywords: outerref, subquery | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
Description changed by Igor Pejic:
Old description:
> After trying to migrate from 2.2. to 3.0, we experience a problem with
> the translation of queries in PostgreSQL which used to work in 2.2.
>
> A breaking test is shown in:
> https://github.com/igorpejic/django/pull/1/files
>
> From investigation this is related to:
> https://code.djangoproject.com/ticket/31094
> and it seems the regression was introduced in:
> https://github.com/django/django/commit/fb3f034f1c63160c0ff13c609acd01c18be12f80
>
> It seems that the combination of the "double OuterRef" with the "Case"
> logic is causing the problem.
>
> Query looks like:
>
> {{{
> books_with_same_name_as_country = Book.objects.filter(
> id__in=Subquery(
> Book.objects.filter(
> name=OuterRef(OuterRef('country__name')),
> ).values('id')
> )
> ).values('id')[:1]
> books_breakdown = Publisher.objects.annotate(total_books=Case(
> When(
> num_awards__gte=2,
> then=Subquery(books_with_same_name_as_country,
> IntegerField())
> ),
> When(
> num_awards__lt=0,
> then=Count('country__publishers')
> ),
> ))
> }}}
>
> Stack trace:
>
> {{{
> ======================================================================
> ERROR: test_group_by_subquery_annotation_with_conditional
> (aggregation.tests.AggregateTestCase)
> ----------------------------------------------------------------------
> Traceback (most recent call last):
> File "/home/igor/django-repo/django/db/backends/utils.py", line 86, in
> _execute
> return self.cursor.execute(sql, params)
> psycopg2.errors.GroupingError: subquery uses ungrouped column
> "aggregation_country.name" from outer query
> LINE 1: ..."id" FROM "aggregation_book" U0 WHERE U0."name" =
> "aggregati...
> ^
>
> The above exception was the direct cause of the following exception:
>
> Traceback (most recent call last):
> File "/home/igor/django-repo/django/test/testcases.py", line 1229, in
> skip_wrapper
> return test_func(*args, **kwargs)
> File "/home/igor/django-repo/tests/aggregation/tests.py", line 1299, in
> test_group_by_subquery_annotation_with_conditional
> self.assertEqual(books_breakdown.get(id=self.p1.id).total_books, 1)
> File "/home/igor/django-repo/django/db/models/query.py", line 411, in
> get
> num = len(clone)
> File "/home/igor/django-repo/django/db/models/query.py", line 258, in
> __len__
> self._fetch_all()
> File "/home/igor/django-repo/django/db/models/query.py", line 1261, in
> _fetch_all
> self._result_cache = list(self._iterable_class(self))
> File "/home/igor/django-repo/django/db/models/query.py", line 57, in
> __iter__
> results = compiler.execute_sql(chunked_fetch=self.chunked_fetch,
> chunk_size=self.chunk_size)
> File "/home/igor/django-repo/django/db/models/sql/compiler.py", line
> 1154, in execute_sql
> cursor.execute(sql, params)
> File "/home/igor/django-repo/django/db/backends/utils.py", line 68, in
> execute
> return self._execute_with_wrappers(sql, params, many=False,
> executor=self._execute)
> File "/home/igor/django-repo/django/db/backends/utils.py", line 77, in
> _execute_with_wrappers
> return executor(sql, params, many, context)
> File "/home/igor/django-repo/django/db/backends/utils.py", line 86, in
> _execute
> return self.cursor.execute(sql, params)
> File "/home/igor/django-repo/django/db/utils.py", line 90, in __exit__
> raise dj_exc_value.with_traceback(traceback) from exc_value
> File "/home/igor/django-repo/django/db/backends/utils.py", line 86, in
> _execute
> return self.cursor.execute(sql, params)
> django.db.utils.ProgrammingError: subquery uses ungrouped column
> "aggregation_country.name" from outer query
> LINE 1: ..."id" FROM "aggregation_book" U0 WHERE U0."name" =
> "aggregati...
> ^
> }}}
New description:
After trying to migrate from 2.2. to 3.0, we experience a problem with the
translation of queries in PostgreSQL which used to work in 2.2.
A breaking test is shown in:
https://github.com/igorpejic/django/pull/1/files
From investigation this is related to:
https://code.djangoproject.com/ticket/31094
and it seems the regression was introduced in:
https://github.com/django/django/commit/fb3f034f1c63160c0ff13c609acd01c18be12f80
It seems that the combination of the "double OuterRef" with the "Case"
logic is causing the problem.
Query looks like:
{{{
books_with_same_name_as_country = Book.objects.filter(
id__in=Subquery(
Book.objects.filter(
name=OuterRef(OuterRef('country__name')),
).values('id')
)
).values('id')[:1]
books_breakdown = Publisher.objects.annotate(total_books=Case(
When(
num_awards__gte=2,
then=Subquery(books_with_same_name_as_country,
IntegerField())
),
When(
num_awards__lt=0,
then=Count('country__publishers')
),
))
}}}
Stack trace:
{{{
======================================================================
ERROR: test_group_by_subquery_annotation_with_conditional
(aggregation.tests.AggregateTestCase)
----------------------------------------------------------------------
Traceback (most recent call last):
File "/home/igor/django-repo/django/db/backends/utils.py", line 86, in
_execute
return self.cursor.execute(sql, params)
psycopg2.errors.GroupingError: subquery uses ungrouped column
"aggregation_country.name" from outer query
LINE 1: ..."id" FROM "aggregation_book" U0 WHERE U0."name" = "aggregati...
^
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/home/igor/django-repo/django/test/testcases.py", line 1229, in
skip_wrapper
return test_func(*args, **kwargs)
File "/home/igor/django-repo/tests/aggregation/tests.py", line 1299, in
test_group_by_subquery_annotation_with_conditional
self.assertEqual(books_breakdown.get(id=self.p1.id).total_books, 1)
File "/home/igor/django-repo/django/db/models/query.py", line 411, in
get
num = len(clone)
File "/home/igor/django-repo/django/db/models/query.py", line 258, in
__len__
self._fetch_all()
File "/home/igor/django-repo/django/db/models/query.py", line 1261, in
_fetch_all
self._result_cache = list(self._iterable_class(self))
File "/home/igor/django-repo/django/db/models/query.py", line 57, in
__iter__
results = compiler.execute_sql(chunked_fetch=self.chunked_fetch,
chunk_size=self.chunk_size)
File "/home/igor/django-repo/django/db/models/sql/compiler.py", line
1154, in execute_sql
cursor.execute(sql, params)
File "/home/igor/django-repo/django/db/backends/utils.py", line 68, in
execute
return self._execute_with_wrappers(sql, params, many=False,
executor=self._execute)
File "/home/igor/django-repo/django/db/backends/utils.py", line 77, in
_execute_with_wrappers
return executor(sql, params, many, context)
File "/home/igor/django-repo/django/db/backends/utils.py", line 86, in
_execute
return self.cursor.execute(sql, params)
File "/home/igor/django-repo/django/db/utils.py", line 90, in __exit__
raise dj_exc_value.with_traceback(traceback) from exc_value
File "/home/igor/django-repo/django/db/backends/utils.py", line 86, in
_execute
return self.cursor.execute(sql, params)
django.db.utils.ProgrammingError: subquery uses ungrouped column
"aggregation_country.name" from outer query
LINE 1: ..."id" FROM "aggregation_book" U0 WHERE U0."name" = "aggregati...
^
}}}
Full query 2.2:
{{{
SELECT "aggregation_regress_publisher"."id",
"aggregation_regress_publisher"."name",
"aggregation_regress_publisher"."num_awards",
"aggregation_regress_publisher"."country_id",
CASE
WHEN "aggregation_regress_publisher"."num_awards" >= 2 THEN
(SELECT V0."id"
FROM "aggregation_regress_book" V0
WHERE V0."id" IN
(SELECT U0."id"
FROM "aggregation_regress_book" U0
WHERE U0."name" =
("aggregation_regress_country"."name")
ORDER BY U0."name" ASC)
ORDER BY V0."name" ASC
LIMIT 1)
WHEN "aggregation_regress_publisher"."num_awards" < 0 THEN
COUNT(T3."id")
ELSE NULL
END AS "total_books"
FROM "aggregation_regress_publisher"
INNER JOIN "aggregation_regress_country" ON
("aggregation_regress_publisher"."country_id" =
"aggregation_regress_country"."id")
LEFT OUTER JOIN "aggregation_regress_publisher" T3 ON
("aggregation_regress_country"."id" = T3."country_id")
GROUP BY "aggregation_regress_publisher"."id",
(SELECT V0."id"
FROM "aggregation_regress_book" V0
WHERE V0."id" IN
(SELECT U0."id"
FROM "aggregation_regress_book" U0
WHERE U0."name" = ("aggregation_regress_country"."name")
ORDER BY U0."name" ASC)
ORDER BY V0."name" ASC
LIMIT 1)
}}}
Full query 3.0:
{{{
SELECT "aggregation_publisher"."id",
"aggregation_publisher"."name",
"aggregation_publisher"."num_awards",
"aggregation_publisher"."duration",
"aggregation_publisher"."country_id",
CASE
WHEN "aggregation_publisher"."num_awards" >= 2 THEN
(SELECT V0."id"
FROM "aggregation_book" V0
WHERE V0."id" IN
(SELECT U0."id"
FROM "aggregation_book" U0
WHERE U0."name" = "aggregation_country"."name")
LIMIT 1)
WHEN "aggregation_publisher"."num_awards" < 0 THEN
COUNT(T3."id")
ELSE NULL
END AS "total_books"
FROM "aggregation_publisher"
INNER JOIN "aggregation_country" ON ("aggregation_publisher"."country_id"
= "aggregation_country"."id")
LEFT OUTER JOIN "aggregation_publisher" T3 ON ("aggregation_country"."id"
= T3."country_id")
GROUP BY "aggregation_publisher"."id"
}}}
--
--
Ticket URL: <https://code.djangoproject.com/ticket/32478#comment:5>
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/067.8c380f0c37673a28980c2c128937432b%40djangoproject.com.
