diff --git a/ykval-db.php b/ykval-db.php
index b133149..fb883b6 100644
--- a/ykval-db.php
+++ b/ykval-db.php
@@ -136,7 +136,8 @@ class Db
    */
   public function updateBy($table, $k, $v, $values)
   {
-    
+    $query = "";
+
     foreach ($values as $key=>$value){
       if (!is_null($value)) $query .= ' ' . $key . "='" . $value . "',";
       else $query .= ' ' . $key . '=NULL,';