No function with name 'F_ITEMCHECK' exists in this scope

Question

Hi i have a error:
SQL> Declare
2 Cursor stk_val is
3 Select prod_code,prod_desc, bal_Stock from prod_tran;
4 mProd_code prod_tran.prod_Code%type;
5 mProd_desc prod_tran.prod_desc%type;
6 mProd_qty prod_tran.prod_qty%type;
7 valexits integer;
8 bal_stock integer;
9 vquantity integer;
10 f_itemcheck integer;
11 Begin
12 Open stk_val;
13 loop
14 Fetch stk_val into mprod_code,mprod_desc,mprod_qty;
15 exit when stk_val%notfound;
16 valexits := f_itemcheck(mprod_code);
17 if valexits = 0 then
18 insert into prod_mast(prod_code,prod_Desc,bal_Stock)
19 values(mprod_code,mprod_Desc,mprod_qty);
20 elsif valexits = 1 then
21 update prod_mast
22 set bal_stock = bal_stock+ vquantity
23 where prod_code=mprod_code;
24 end if;
25 end loop;
26 close stk_Val;
27 end;
28 /
Declare
ERROR at line 1:
ORA-06550: line 3, column 34:
PLS-00320: the declaration of the type of this expression is incomplete or malformed
ORA-06550: line 3, column 6:
PL/SQL: SQL Statement ignored
ORA-06550: line 16, column 22:
PLS-00222: no function with name 'F_ITEMCHECK' exists in this scope
ORA-06550: line 16, column 10:
PL/SQL: Statement ignored

Answer 1

May be try this code
Declare
  Cursor stk_val is
  Select prod_code,prod_desc, bal_Stock
    from prod_tran;
  v_prod stk_val%rowtype;
  valexits    integer;
  bal_stock   integer;
  vquantity   integer;
Begin
  Open stk_val;
  loop
    Fetch stk_val into v_prod;
    exit when stk_val%notfound;     
    valexits := f_itemcheck(v_prod.prod_code);
    if valexits = 0 then       
      insert into prod_mast(prod_code,prod_Desc,bal_Stock)
      values(v_prod.prod_code,v_prod.prod_Desc,v_prod.prod_qty);
    elsif valexits = 1 then
      update prod_mast
         set bal_stock = bal_stock+ vquantity
       where prod_code=v_prod.prod_code;
    end if;
  end loop;
  close stk_Val;
end;Note: Code untested