Replications steps:

1. Create a forum
   1. While editing the settings set the following
      1. Whole forum grading - Grade - Type "Scale"
      2. Scale should be "Default competence scale"
      3. Ratings - Aggregate type - Average of ratings
      4. Type "Scale"
      5. Scale should also be "Default competence scale"
      6. Save and display
2. While in the forum activity add the "Activity results" block.
3. Configure the Activity results block.
4. Observe the warning at the top.

   Error: mdb->get_record() found more than one record!

   line 1683 of /lib/dml/moodle_database.php: call to debugging()

   line 1643 of /lib/dml/moodle_database.php: call to moodle_database->get_record_sql()

   line 1622 of /lib/dml/moodle_database.php: call to moodle_database->get_record_select()

   line 100 of /blocks/activity_results/block_activity_results.php: call to moodle_database->get_record()

   line 66 of /blocks/activity_results/edit_form.php: call to block_activity_results->get_owning_activity()

   line 70 of /blocks/edit_form.php: call to block_activity_results_edit_form->specific_definition()

   line 214 of /lib/formslib.php: call to block_edit_form->definition()

   line 63 of /blocks/edit_form.php: call to moodleform->__construct()

   line 1664 of /lib/blocklib.php: call to block_edit_form->__construct()

   line 1409 of /lib/blocklib.php: call to block_manager->process_url_edit()

   line 1501 of /lib/pagelib.php: call to block_manager->process_url_actions()

   line 985 of /lib/pagelib.php: call to moodle_page->starting_output()

   line 1299 of /lib/outputrenderers.php: call to moodle_page->set_state()

   line 156 of /mod/forum/view.php: call to core_renderer->header()