diff --git a/webapp/controller/BaseAuthedController.class.php b/webapp/controller/BaseAuthedController.class.php
index 02e6c1b9..84824e70 100644
--- a/webapp/controller/BaseAuthedController.class.php
+++ b/webapp/controller/BaseAuthedController.class.php
@@ -440,7 +440,7 @@ class BaseAuthedController extends BaseController {
         {
             $this->_updateUserInfo(array(
                 'gold' => function () use($itemNum) {
-                    return "GREATEST(0, gold - ${itemNum})";
+                    return "gold - ${itemNum}";
                 },
                 'consume_gold' => function () use ($itemNum){
                     return "consume_gold + ${itemNum}";