private function replaceConstants(Gpf_Data_Record $row) {
$coupon = new Pap_Db_Coupon();
$coupon->setId($row->get('id'));
$coupon->setCode($row->get('code'));
$coupon->setStatus($row->get('status'));
$coupon->set(Pap_Db_Table_Coupons::MAX_USE_COUNT, $row->get('limit_use'));
$coupon->set(Pap_Db_Table_Coupons::VALID_FROM, $row->get('valid_from'));
$coupon->set(Pap_Db_Table_Coupons::VALID_TO, $row->get('valid_to'));
$row->add('coupon', $this->banner->getCouponText($coupon));
$row->add('validity', $coupon->isValid());
}