Scalar function to get lastest currency rate from SAP Business One HANA

POLR_LATEST_CURRENCY_RATE.sql

ALTER FUNCTION POLR_LATEST_CURRENCY_RATE(CurrencyCode char(3))
RETURNS result decimal(15,2)
LANGUAGE SQLSCRIPT  
SQL SECURITY INVOKER AS
BEGIN	
	DECLARE found INT := 0;
	SELECT COUNT(1) INTO found FROM "ORTT" WHERE "Currency" = :CurrencyCode AND "RateDate" <= CURRENT_DATE;
	
	IF :found > 0
	THEN
		SELECT "Rate" INTO result FROM "ORTT" WHERE "Currency" = :CurrencyCode AND "RateDate" <= CURRENT_DATE ORDER BY "RateDate" DESC LIMIT 1;
	ELSE 
		SELECT 1 INTO result FROM "DUMMY";
	END IF;

END;