#28408: Inconsistant error message for trying to update an annotated F expression -------------------------------------+------------------------------------- Reporter: Kevin | Owner: (none) Marsh | Type: | Status: new Uncategorized | Component: Error | Version: 1.11 reporting | Severity: Normal | Keywords: annotate, F, update Triage Stage: | Has patch: 0 Unreviewed | Needs documentation: 0 | Needs tests: 0 Patch needs improvement: 0 | Easy pickings: 0 UI/UX: 0 | -------------------------------------+------------------------------------- I ran into a bit of a nasty error yesterday on Django 1.11, Postgres 9.5 where I was trying to do an update using an `F` expression where the value in that expression referred to an annotation of an annotation, each using a `Case` statement inside the annotation. The error message it was giving me was something like the following:
{{{ ProgrammingError Traceback (most recent call last) <ipython-input-1-29e48364245c> in <module>() ----> 1 MyModel.objects.causing_problems() /usr/src/app/apps/myapp/managers.py in causing_problems(self) 833 ).update( --> 834 my_field=F('my_annotated_field'), 835 ) 836 /usr/src/app/apps/django/db/models/query.py in update(self, **kwargs) 645 query._annotations = None 646 with transaction.atomic(using=self.db, savepoint=False): --> 647 rows = query.get_compiler(self.db).execute_sql(CURSOR) 648 self._result_cache = None 649 return rows /usr/src/app/apps/django/db/models/sql/compiler.py in execute_sql(self, result_type) 1189 related queries are not available. 1190 """ -> 1191 cursor = super(SQLUpdateCompiler, self).execute_sql(result_type) 1192 try: 1193 rows = cursor.rowcount if cursor else 0 /usr/src/app/apps/django/db/models/sql/compiler.py in execute_sql(self, result_type, chunked_fetch) 884 # silencing when dropping Python 2 compatibility. 885 pass --> 886 raise original_exception 887 888 if result_type == CURSOR: ProgrammingError: missing FROM-clause entry for table "myapp_mymodel" LINE 1: ...false END, "a_field" = CASE WHEN CASE WHEN ("myapp_my... }}} Spent a while trying to debug where it was going wrong, ended up narrowing down the problem to trying to update a field using an `F` expression on an annotated field which included a join in it. I'm not sure if better error message would have helped in my case but in the much simpler test attached it'd be usfeul if the first and second assertions raised the same or similar error message. -- Ticket URL: <https://code.djangoproject.com/ticket/28408> 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 django-updates+unsubscr...@googlegroups.com. To post to this group, send email to django-updates@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/django-updates/053.f77bcfd10f528155c622629f6f0a4d79%40djangoproject.com. For more options, visit https://groups.google.com/d/optout.