关于Adodb连接查询sql语句出错？

<?php
/*

 adodb数据库学习

 */

 include_once("adodb5/adodb.inc.php");//包含adodb的文件
$db = NewADOConnection('mysql');
   $db->Connect("localhost", "root", "", "member
");

   $db->Execute("set names 'GBK'");
   $q=$db->Execute("select * from user_list
");
$row=$q->FetchRow();



?>
为什么在这一句$row=$q->FetchRow();出现这句错误：Fatal error: Call to a member function FetchRow() on a non-object in E:\PHPWEB\test\adob.php on line 13