diff --git a/advlabdb/customClasses.py b/advlabdb/customClasses.py
index fa3f2c9..43b8b81 100644
--- a/advlabdb/customClasses.py
+++ b/advlabdb/customClasses.py
@@ -159,11 +159,18 @@ class CustomModelView(ModelView):
             return model
 
     def customUpdateModel(self, form, model):
+        """
+        Retrun True if something changed during update, False otherwise.
+        """
         form.populate_obj(model)
+        # No way to know if something changed. Therefore, return True anyway.
+        return True
 
     def update_model(self, form, model):
         try:
-            self.customUpdateModel(form, model)
+            if self.customUpdateModel(form, model) is False:
+                # Nothing changed
+                return True
 
             self.on_model_change(form, model, False)
             self.session.commit()