OrderCompatibility::getAvailableFields

static function getAvailableFields()
{
	$registry = SaleRegistry::getInstance(static::getRegistryType());
	/** @var SaleOrder $orderClassName */
	$orderClassName = $registry->getOrderClassName();

	return array_merge($orderClassName::getAvailableFields(),
						array('PRICE_DELIVERY', "PAY_VOUCHER_DATE", "PAY_VOUCHER_NUM", "DATE_ALLOW_DELIVERY", "DATE_PAYED")
	);
}