public function getEvent($pspReference, $adyenEventCode, $success = null)
    {
        $db = $this->_getReadAdapter();

        if ($success == null) {
            $sql = $db->select()
                ->from($this->getMainTable(), array('*'))
                ->where('adyen_event_code = ?', $adyenEventCode)
                ->where('psp_reference = ?', $pspReference);
        } else {
            $sql = $db->select()
                ->from($this->getMainTable(), array('*'))
                ->where('adyen_event_code = ?', $adyenEventCode)
                ->where('psp_reference = ?', $pspReference)
                ->where('success = ?', $success);
        }

        $stmt = $db->query($sql);
        return $stmt->fetch();
    }