diff --git a/mod/quiz/locallib.php b/mod/quiz/locallib.php
index ea82013443f..8bacae7129c 100644
--- a/mod/quiz/locallib.php
+++ b/mod/quiz/locallib.php
@@ -1624,6 +1624,9 @@ function quiz_groups_group_deleted_handler($event) {
              WHERE quiz.course = :courseid AND grp.id IS NULL";
     $params = array('courseid'=>$event->courseid);
     $records = $DB->get_records_sql_menu($sql, $params);
+    if (!$records) {
+        return; // Nothing to do.
+    }
     $DB->delete_records_list('quiz_overrides', 'id', array_keys($records));
     quiz_update_open_attempts(array('quizid'=>array_unique(array_values($records))));
 }