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
23877	Aggregation over subquery doesn't ensure the subquery has needed columns	Anssi Kääriäinen	nobody	"When aggregating over a subquery (result of `.annotate().aggregate()` queries for example), then Django doesn't ensure the subquery has the target of the aggregation included in the subquery's SELECT clause.

An example query is
{{{
        Book.objects.annotate(avg_price=Avg('price')).aggregate(
            publisher_awards=Sum('publisher__num_awards')
        )
}}}
Here, the `Sum('publisher__num_awards')` creates correctly a join to publisher, but the num_awards column of the publisher table is not selected in the generated subquery. As the column is not present in the subquery, the database generates an error for the `SUM(""subquery"".""num_awards"") FROM (...) subquery` SQL generated by Django.

To fix this we need to make sure that aggregations over a subquery has all the base columns it needs added to the inner query.

This bug seems to have existed always in Django. I'll mark as master as that is where this should be fixed.
"	Bug	closed	Database layer (models, ORM)	dev	Normal	fixed			Accepted	1	0	0	1	0	0