create or replace FUNCTION CALINTEREST
( DNumber IN VARCHAR2,
  IRate IN NUMBER
) RETURN NUMBER IS
    AInterest NUMERIC(17,8):=0;
    PDue NUMERIC(11,2);
    IDue NUMERIC(17,8);
    INTRate NUMERIC(5,2);
    IntDate DATE;
    IntDATEDIFF NUMERIC(6):=0;
BEGIN
BEGIN
  SELECT
  DBRD_PRI_DUE,
  DBRD_INT_DUE,
  DBRD_INT_RATE,
  DBRD_INT_DATE INTO
            PDue
            ,IDue
            ,INTRate
            ,IntDate
        FROM
            DBRD
        WHERE
            DBRNO = DNumber;

        IF(INTRate = 999)
    THEN
             INTRate := IRate;
        END IF;
    IntDATEDIFF:=Cast((Sysdate-IntDate) AS NUMBER(11,0));
        AInterest := IDue + (PDue * INTRate * IntDATEDIFF / 365 / 100);
   END;
  RETURN AInterest;
END;