Index: autoassignrole-admin.inc
===================================================================
--- autoassignrole-admin.inc
+++ autoassignrole-admin.inc
@@ -356,9 +356,7 @@
   db_query($sql, $form_state['values']['user_selection'], 'user_selection');
   db_query($sql, $form_state['values']['auto_admin_active'], 'auto_admin_active');
   preg_match('/\[nid:(\d+)\]/', $form_state['values']['node_user_register'], $matches);
-  if (isset($matches[1])) {
-    db_query($sql, $matches[1], 'node_user_register');
-  }
+  db_query($sql, isset($matches[1]) ? $matches[1] : '', 'node_user_register');