From 92f39a58a7d6fbfa0752c029dff61c9d234bed70 Mon Sep 17 00:00:00 2001
From: Tim Metzler <tim.metzler@h-brs.de>
Date: Mon, 6 Apr 2020 15:57:54 +0200
Subject: [PATCH] Handle bug when assignment contains several notebooks

---
 nbgrader/server_extensions/formgrader/gradeexporter.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/nbgrader/server_extensions/formgrader/gradeexporter.py b/nbgrader/server_extensions/formgrader/gradeexporter.py
index e4bee20a2..d7d0925ef 100644
--- a/nbgrader/server_extensions/formgrader/gradeexporter.py
+++ b/nbgrader/server_extensions/formgrader/gradeexporter.py
@@ -151,6 +151,7 @@ def get_notebook_grades(self):
         .filter(Notebook.assignment_id == Assignment.id) \
         .filter(SubmittedAssignment.assignment_id == Assignment.id) \
         .filter(SubmittedNotebook.assignment_id == SubmittedAssignment.id) \
+        .filter(SubmittedNotebook.notebook_id == Notebook.id) \
         .filter(Grade.notebook_id == SubmittedNotebook.id) \
         .group_by(SubmittedAssignment.student_id) \
         .all()