Invoke a function from a procedure - sql

Question

I am trying to create a PL/SQL procedure that will invoke a function I called GET_HIGHORDER_FUNC which is already working:
create or replace FUNCTION GET_HIGHORDER_FUNC
return number
AS
c_hiorder number;
BEGIN
select max(sum(product.product_standardprice * orderline.ordered_quantity)) into c_hiorder
from customer, product, orderline, orders
where customer.customer_id = orders.customer_id
and orders.order_id = orderline.order_id
and orderline.product_id = product.product_id
group by customer_name;
RETURN c_hiorder;
END GET_HIGHORDER_FUNC;
create or replace procedure PRINT_CUST_PROC(
p_hiordername in number)
as
begin
/* This procedure should show the name of the customer who have the highest
amount of order which will be available upon invoking the function above */
end;

Answer 1

Just invoke it as you would with any function?
This is how i would try based on your latest comments
create or replace FUNCTION GET_HIGHORDER_FUNC(c_customer_name out varchar2,c_hiorder out int)
return number
AS
c_hiorder number;
BEGIN
select y.customer_name
,y.summed_price
into customer_name
,c_hiorder
from (
select x.customer_name
,x.summed_price
,row_number() over(order by x.summed_price desc) as rnk
from (
select customer_name
,sum(product.product_standardprice * orderline.ordered_quantity) as summed_price
from customer, product, orderline, orders
where customer.customer_id = orders.customer_id
and orders.order_id = orderline.order_id
and orderline.product_id = product.product_id
group by customer_name
)x
)y
where y.rnk=1;
RETURN 1;
END GET_HIGHORDER_FUNC;
create or replace procedure PRINT_CUST_PROC(
p_hiordername in number)
as
l_return int;
l_customer_name varchar2(1000);
l_hiorder int;
begin
/* This procedure should show the name of the customer who have the highest
amount of order which will be available upon invoking the function above
*/
l_return : = GET_HIGHORDER_FUNC(l_customer_name,l_hiorder);
dbms_output.put_line(l_customer_name);
dbms_output.put_line(l_hiorder);
end;