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
28374	Updating an Annotated Queryset results in ProgrammingError	quindraco	nobody	"I have a model called ""item"" in an app called ""PoliceInventory"".  I have a View for updating this model from a form, which inherits from DetailView and UpdateView.  Note that I am leaving out code I believe to be irrelevant, but can provide more if needed.  I am running 1.11.3 (to make sure I have the new fix for #19513, which I believe to be the same bug).  I have placed a comment in the code below where the ProgrammingError is thrown.  This is in Python 3.5.2.

ProgrammingError:
{{{
ProgrammingError at /PoliceInventory/item/update/1

subquery has too many columns
LINE 1: ... ""type"" = '9mm' WHERE ""PoliceInventory_item"".""id"" IN (SELECT...
}}}

The real sql query, mogrified from the cursor (Postgres 9.6, psycopg2)
{{{
UPDATE ""PoliceInventory_item"" 
SET ""_created"" = '2017-05-23T16:15:46.562060'::timestamp,
     ""_created_by_id"" = 1,
     ""_last_updated"" = '2017-07-07T09:10:23.234226'::timestamp,
     ""_last_updated_by_id"" = 2,
     ""brand_id"" = 3,
     ""type"" = '9mm' 
WHERE ""PoliceInventory_item"".""id"" IN (SELECT U0.""id"" AS Col1,
     CONCAT(
        CONCAT(U1.""name""::text,'')::text,
		CONCAT(' '::text,
               CONCAT(U0.""type""::text,'')
              )
     ) AS ""annotateString"" 
FROM ""PoliceInventory_item"" U0 
INNER JOIN ""PoliceInventory_brand"" U1 
ON (U0.""brand_id"" = U1.""id"") 
WHERE U0.""id"" = 1);
}}}

Manager, model, and view code:
{{{
class customManager(models.Manager):
    def get_queryset(self):
        return self.model.annotateObjects(super().get_queryset())

    def asked_by(self, asker=None):
        return self.model.annotateObjects(self.get_queryset(), asker=asker) #this annotates the Model; I can provide how, if helpful.

class customModel(models.Model):
    objects = customManager()
    class Meta:
        base_manager_name = 'objects'

class ViewObject(django.views.generic.DetailView,django.views.generic.UpdateView):
    def form_valid(self, form):
        obj = form.save(commit=False)
        obj._last_updated_by = self.user
        obj.save() #CRASH HAPPENS HERE
        form.save_m2m()
        self.object = obj
        return super().form_valid(form)
}}}

The bug is fairly obvious - the annotation, in this case named annotateString, is being held onto for no apparent reason.  The following code is how I am currently fixing it, inside my customModel class, but it has some pretty obvious major flaws:

{{{
    def _do_update(self, *args, **kwargs):
        if 'base_qs' in kwargs:
            original = kwargs['base_qs']
        else:
            original = args[0]
        if original.query.annotations:
            c = original.all()
            c.query.annotations.clear()
            c.filter(pk__in=original.values_list('pk', flat=True))
            if 'base_qs' in kwargs:
                kwargs['base_qs'] = c
            else:
                args = list(args)
                args[0] = c
                args = tuple(args)
        return super()._do_update(*args,**kwargs)
}}}"	Bug	closed	Database layer (models, ORM)	1.11	Normal	needsinfo	QuerySet Update Annotation Generic View Form		Unreviewed	0	0	0	0	0	0