id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
36292	Annotating an aggregate function over a group including annotations or transforms followed by a column references crashes with IndexError	Patrick Altman	Simon Charette	"When I upgraded to 5.2 today, a number of my query sets broke tracebacks on building the query.  I didn't notice anything in the BIC of the release notes. 

I tossed together a project to make it easier to clone and repro:
https://github.com/paltman/groupby-demo-dj52

But in summary, when I have some models like:

{{{
from django.db import models


class Bag(models.Model):
    kind = models.PositiveBigIntegerField(unique=True)


class Order(models.Model):
    blended_at = models.DateTimeField(null=True, default=None)
    gross_weight = models.FloatField(null=True, default=None)
    tare_weight = models.FloatField(null=True, default=None)
    total_tons = models.FloatField(null=True, default=None)
    blend_status = models.CharField(max_length=2, blank=True)
    bag_type = models.ForeignKey(Bag, on_delete=models.CASCADE, null=True)
}}}

and try to build a queryset like:

{{{
from django.db.models import Case, When, F, FloatField, Value, Sum

from .models import Order


TONS_ANNOTATION = dict(
    blended_tons=Case(
        When(
            gross_weight__gt=0,
            then=(F(""gross_weight"") - F(""tare_weight"")) / Value(2000)
        ),
        default=F(""total_tons""),
        output_field=FloatField()
    )
)

dry_tons = Order.objects.filter(
    blended_at__date__range=[""2025-03-01"", ""2025-03-31""],
).annotate(
    **TONS_ANNOTATION
).values(
    ""blend_status"",
    ""blended_at__date"",
    ""bag_type__kind"",
).annotate(
    tons=Sum(""blended_tons"")
)
}}}

I get the following traceback when trying to just print the query out:

{{{
>>> print(dry_tons.query)
Traceback (most recent call last):
  File ""<console>"", line 1, in <module>
  File ""/usr/local/lib/python3.13/site-packages/django/db/models/sql/query.py"", line 342, in __str__
    sql, params = self.sql_with_params()
                  ~~~~~~~~~~~~~~~~~~~~^^
  File ""/usr/local/lib/python3.13/site-packages/django/db/models/sql/query.py"", line 350, in sql_with_params
    return self.get_compiler(DEFAULT_DB_ALIAS).as_sql()
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^
  File ""/usr/local/lib/python3.13/site-packages/django/db/models/sql/compiler.py"", line 765, in as_sql
    extra_select, order_by, group_by = self.pre_sql_setup(
                                       ~~~~~~~~~~~~~~~~~~^
        with_col_aliases=with_col_aliases or bool(combinator),
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    )
    ^
  File ""/usr/local/lib/python3.13/site-packages/django/db/models/sql/compiler.py"", line 85, in pre_sql_setup
    self.setup_query(with_col_aliases=with_col_aliases)
    ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ""/usr/local/lib/python3.13/site-packages/django/db/models/sql/compiler.py"", line 74, in setup_query
    self.select, self.klass_info, self.annotation_col_map = self.get_select(
                                                            ~~~~~~~~~~~~~~~^
        with_col_aliases=with_col_aliases,
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    )
    ^
  File ""/usr/local/lib/python3.13/site-packages/django/db/models/sql/compiler.py"", line 286, in get_select
    expression = cols[expression]
                 ~~~~^^^^^^^^^^^^
IndexError: tuple index out of range
}}}

Posted here earlier: https://forum.djangoproject.com/t/my-group-by-aggregations-are-breaking-in-5-2/40162/1 but after I posted I realized this seems like a bug just in the fact that it's been working for a while now in previous versions.
"	Bug	closed	Database layer (models, ORM)	5.2	Release blocker	fixed		Patrick Altman	Ready for checkin	1	0	0	0	0	0