fixed notce

CRM/Dataprocessor/Form/Source.php

@@ -88,6 +88,7 @@ class CRM_Dataprocessor_Form_Source extends CRM_Core_Form {
     $this->assign('is_first_data_source', $this->isFirstDataSource);
 
     $type = CRM_Utils_Request::retrieve('type', 'String');
+    $table_name = false;
     if ($type) {
       $this->source['type'] = $type;
       if ($type==='sqltable') {