在foreach中的Joomla sql事务

What do you think about this block of code? I wan't to execute all queries from array.

foreach($sql_array as $sql) {
     try {

        $this->_db->transactionStart();
        $this->_db->setQuery((string)$sql)->execute();
        $this->_db->transactionCommit();

     } catch (Exception $e) {
        $this->_db->transactionRollback();
        JErrorPage::render($e);
     }
}

Or should I move $this->_db->transactionStart(); before foreach statement?