prevent duplication of template values

db/install.php

@@ -38,8 +38,10 @@ function xmldb_attendance_install() {
         $rec->grade = $v;
         $rec->visible = 1;
         $rec->deleted = 0;
+        if (!$DB->record_exists('attendance_statuses', array('attendanceid' => 0, 'acronym' => $rec->acronym))) {
             $result = $result && $DB->insert_record('attendance_statuses', $rec);
         }
+    }
 
     return $result;
 }