我用了官方说的方法怎么也连接不起ACCESS数据库呀

'DB_CONFIG2'=> array(
"DB_TYPE"=> "pdo",
'DB_DSN'=>'odbc:DRIVER={Microsoft Access Driver (*.mdb)};DBQ='.APP_PATH. 'db\test.mdb',
'DB_USER'=>'',
'DB_PWD'=>'',
'DB_PREFIX'=>'',
),

$content = M('Content',Null,'DB_CONFIG2');
$dao=$content->select();