Question

I have the following models:

class Work(models.Model):
    visible = models.BooleanField(default=False)

class Book(models.Model):
    work = models.ForeignKey('Work')    

I am attempting to update some rows like so:

qs=Work.objects.all()
qs.annotate(Count('book')).filter(Q(book__count__gt=1)).update(visible=False)

However, this is giving an error:

DatabaseError: subquery has too many columns
LINE 1: …SET “visible” = false WHERE “app_work”.”id” IN (SELECT…

If I remove the update clause, the query runs with no problems and returns what I am expecting.

It looks like this error happens for queries with an annotate followed by an update. Is there some other way to write this?

Answer 1

Without making a toy database to be able to duplicate your issue and try out solutions, I can at least suggest the approach in Django: Getting complement of queryset as one possible approach.

Try this approach:

qs.annotate(Count('book')).filter(Q(book__count__gt=1))
Work.objects.filter(pk__in=qs.values_list('pk', flat=True)).update(visible=False)