Zend Framework のトランザクション処理に関する質問

<?php<br />
<br />
// 创建一个 $db对象, 然后开始做一个事务处理.<br />
$db->beginTransaction();<br />
<br />
// 尝试数据库操作.<br />
// 假如成功,commit该操作;<br />
// 假如, roll back.<br />
try {<br />
    $db->query(...);<br />
    $db->commit();<br />
} catch (Exception $e) {<br />
    $db->rollBack();<br />
    echo $e->getMessage();<br />
}<br />
<br />
?>

<br />
[general]<br />
db.adapter = PDO_MYSQL<br />
db.config.host = localhost<br />
db.config.username = root<br />
db.config.password = 123456<br />
db.config.dbname = testdb <br />
db.config.charset = utf8<br />
date_default_timezone = "PRC"<br />

<br>
<?php<br />
require_once 'Zend/Config/Exception.php';<br />
require_once 'Zend/Config/Ini.php';<br />
require_once 'Zend/Registry.php';<br />
require_once 'Zend/Db.php';<br />
require_once 'Zend/Db/Table.php';<br />
//require_once 'common/Blowfish.php';<br />
//require_once 'common/Hosts.php';<br />
クラス Common_Util<br />
{ <br />
public static function getDb($configName,$setcharset=false)<br />
{<br />
if($configName)<br />
{<br />
$config=new Zend_Config_Ini('../config.ini',$configName);<br />
$registry= Zend_Registry::getInstance();<br />
$registry->set('config',$config);<br />
$params=$config->db->config->toArray();<br />
$params['options']=array(PDO::ATTR_PERSISTENT => true);<br>
$db = Zend_Db::factory($config->db->adapter,$params);