#36405: Aggregates with order_by using OuterRef raise FieldError
-------------------------------------+-------------------------------------
     Reporter:  Adam Johnson         |                    Owner:  Adam
                                     |  Johnson
         Type:  Bug                  |                   Status:  assigned
    Component:  Database layer       |                  Version:  5.2
  (models, ORM)                      |
     Severity:  Release blocker      |               Resolution:
     Keywords:                       |             Triage Stage:  Accepted
    Has patch:  1                    |      Needs documentation:  0
  Needs tests:  0                    |  Patch needs improvement:  0
Easy pickings:  0                    |                    UI/UX:  0
-------------------------------------+-------------------------------------
Changes (by Adam Johnson):

 * version:  dev => 5.2


Old description:

> While fixing #36404, I spotted the same mistake had been made for the
> newly added `Aggregate.order_by` from #35444.

New description:

 While fixing #36404, I spotted the same mistake had been made for
 `Aggregate.order_by` (on `main`, from #35444), which was previously the
 PostgreSQL-specific `OrderableAggMixin.order_by` (on 5.2).

 The issue is reproduced ​in [https://github.com/adamchainz/django-
 ticket-36408 this example project], with models:

 {{{#!python
 from django.db import models


 class Book(models.Model):
     position = models.IntegerField()


 class Chapter(models.Model):
     book = models.ForeignKey(Book, on_delete=models.CASCADE)
 }}}

 And `QuerySet`:

 {{{#!python
 from django.contrib.postgres.aggregates import ArrayAgg
 from django.db.models import OuterRef, Subquery

 from example.models import Book, Chapter

 Book.objects.annotate(
     chapter_ids=Subquery(
         Chapter.objects.annotate(
             ids=ArrayAgg(
                 "id",
                 order_by=[OuterRef("position")],
             )
         ).values("ids")[:1]
     )
 )
 }}}

 This error occurs:

 {{{
 $ python t.py
 Traceback (most recent call last):
     File "/.../t.py", line 15, in <module>
     Chapter.objects.annotate(
     ~~~~~~~~~~~~~~~~~~~~~~~~^
         ids=ArrayAgg(
         ^^^^^^^^^^^^^
     ...<2 lines>...
         )
         ^
     ).values("ids")[:1]
     ^
     File "/.../django/db/models/manager.py", line 87, in manager_method
     return getattr(self.get_queryset(), name)(*args, **kwargs)
             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^
     File "/.../django/db/models/query.py", line 1647, in annotate
     return self._annotate(args, kwargs, select=True)
             ~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^
     File "/.../django/db/models/query.py", line 1699, in _annotate
     clone.query.add_annotation(
     ~~~~~~~~~~~~~~~~~~~~~~~~~~^
         annotation,
         ^^^^^^^^^^^
         alias,
         ^^^^^^
         select=select,
         ^^^^^^^^^^^^^^
     )
     ^
     File "/.../django/db/models/sql/query.py", line 1218, in
 add_annotation
     annotation = annotation.resolve_expression(self, allow_joins=True,
 reuse=None)
     File "/.../django/contrib/postgres/aggregates/mixins.py", line 33, in
 resolve_expression
     return super().resolve_expression(*args, **kwargs)
             ~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^
     File "/.../django/db/models/aggregates.py", line 63, in
 resolve_expression
     c = super().resolve_expression(query, allow_joins, reuse, summarize)
     File "/.../django/db/models/expressions.py", line 300, in
 resolve_expression
     expr.resolve_expression(query, allow_joins, reuse, summarize)
     ~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
     File "/.../django/db/models/expressions.py", line 300, in
 resolve_expression
     expr.resolve_expression(query, allow_joins, reuse, summarize)
     ~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
     File "/.../django/db/models/expressions.py", line 941, in
 resolve_expression
     col = super().resolve_expression(*args, **kwargs)
     File "/.../django/db/models/expressions.py", line 902, in
 resolve_expression
     return query.resolve_ref(self.name, allow_joins, reuse, summarize)
             ~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
     File "/.../django/db/models/sql/query.py", line 2049, in resolve_ref
     join_info = self.setup_joins(
         field_list, self.get_meta(), self.get_initial_alias(),
 can_reuse=reuse
     )
     File "/.../django/db/models/sql/query.py", line 1900, in setup_joins
     path, final_field, targets, rest = self.names_to_path(
                                         ~~~~~~~~~~~~~~~~~~^
         names[:pivot],
         ^^^^^^^^^^^^^^
     ...<2 lines>...
         fail_on_missing=True,
         ^^^^^^^^^^^^^^^^^^^^^
     )
     ^
     File "/.../django/db/models/sql/query.py", line 1805, in names_to_path
     raise FieldError(
     ...<2 lines>...
     )
 django.core.exceptions.FieldError: Cannot resolve keyword 'position' into
 field. Choices are: book, book_id, id
 }}}

 This error again bisects to e306687a3a5507d59365ba9bf545010e5fd4b2a8. The
 cause is similar: duplicate `OuterRef` resolution occurs due to a clause
 left in `OrderableAggMixin.resolve_expression()`.

--
-- 
Ticket URL: <https://code.djangoproject.com/ticket/36405#comment:3>
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 visit 
https://groups.google.com/d/msgid/django-updates/01070196f7a816e5-395d1037-7437-40bb-a285-8f8bc63050d7-000000%40eu-central-1.amazonses.com.

Reply via email to