DECLARE
        --Varchar(100) or Number
      l_car Varchar(100);
      l_part Varchar(100);
    BEGIN
      SELECT CAR_ID, PART_ID INTO l_car, l_part FROM CAR_PARTS WHERE CAR_ID = :P99_CAR AND PARTS_ID = :P99_PARTS;
          IF l_car IS NULL OR l_parts IS NULL THEN
              INSERT INTO CAR_PARTS (CAR_ID, PARTS_ID, CUR_AMOUNT) VALUES (:P99_CAR, :P99_PARTS, :P99_AMOUNT);
      ELSE
          UPDATE CAR_PARTS
              SET CAR_ID = :P99_CAR,
                  PARTS_ID = :P99_PARTS,
                  CUR_AMOUNT = CUR_AMOUNT + :P99_AMOUNT
                      WHERE CAR_ID = :P99_CAR_ID AND PARTS_ID = :P99_PARTS_ID;
         END IF;
     END;