>

>
>&& opening stock table
>create  cursor open_stock (dates d(8),codes c(4),products c(15),qty n(3),rate n(6,2),amount n(6,2))
>insert into open_stock values({^2009-07-01},'1401','Coke 250ml',2,14.45,0)
>insert into open_stock values({^2009-07-01},'1402','Coke 500lm',3,28.90,0)
>replace all amount with qty*rate
>
>&& purchase table
>create  cursor purchase (dates d(8),codes c(4),products c(15),qty n(3),rate n(6,2),amount n(6,2))
>insert into purchase values({^2009-07-02},'1401','Coke 250ml',2,15.30,0)
>insert into purchase values({^2009-07-04},'1401','Coke 250ml',4,16.80,0)
>insert into purchase values({^2009-07-06},'1401','Coke 250ml',6,13.25,0)
>insert into purchase values({^2009-07-03},'1402','Coke 500lm',1,32.75,0)
>insert into purchase values({^2009-07-05},'1402','Coke 500lm',5,24.25,0)
>insert into purchase values({^2009-07-07},'1402','Coke 500lm',9,33.00,0)
>replace all amount with qty*rate
>
>&& sale table
>create  cursor sales (dates d(8),codes c(4),products c(15),qty n(3),rate n(6,2),amount n(6,2))
>insert into sales values({^2009-07-03},'1401','Coke 250ml',1,18.25,0)
>insert into sales values({^2009-07-05},'1401','Coke 250ml',4,19.50,0)
>insert into sales values({^2009-07-07},'1401','Coke 250ml',3,16.75,0)
>insert into sales values({^2009-07-05},'1402','Coke 500lm',1,36.00,0)
>insert into sales values({^2009-07-08},'1402','Coke 500lm',2,28.25,0)
>insert into sales values({^2009-07-10},'1402','Coke 500lm',4,35.50,0)
>replace all amount with qty*rate
>
>

>Sir, I need Closing Stock value as shown in image

Try

&& opening stock table
create  cursor open_stock (dates d(8),codes c(4),products c(15),qty n(3),rate n(6,2),amount n(6,2))
insert into open_stock values({^2009-07-01},'1401','Coke 250ml',2,14.45,0)
insert into open_stock values({^2009-07-01},'1402','Coke 500lm',3,28.90,0)
replace all amount with qty*rate

&& purchase table
create  cursor purchase (dates d(8),codes c(4),products c(15),qty n(3),rate n(6,2),amount n(6,2))
insert into purchase values({^2009-07-02},'1401','Coke 250ml',2,15.30,0)
insert into purchase values({^2009-07-04},'1401','Coke 250ml',4,16.80,0)
insert into purchase values({^2009-07-06},'1401','Coke 250ml',6,13.25,0)
insert into purchase values({^2009-07-03},'1402','Coke 500lm',1,32.75,0)
insert into purchase values({^2009-07-05},'1402','Coke 500lm',5,24.25,0)
insert into purchase values({^2009-07-07},'1402','Coke 500lm',9,33.00,0)
replace all amount with qty*rate

&& sale table
create  cursor sales (dates d(8),codes c(4),products c(15),qty n(3),rate n(6,2),amount n(6,2))
insert into sales values({^2009-07-03},'1401','Coke 250ml',1,18.25,0)
insert into sales values({^2009-07-05},'1401','Coke 250ml',4,19.50,0)
insert into sales values({^2009-07-07},'1401','Coke 250ml',3,16.75,0)
insert into sales values({^2009-07-05},'1402','Coke 500lm',1,36.00,0)
insert into sales values({^2009-07-08},'1402','Coke 500lm',2,28.25,0)
insert into sales values({^2009-07-10},'1402','Coke 500lm',4,35.50,0)
replace all amount with qty*rate

SELECT O.Codes as [Code], O.Products, ;
OpeningQty as [OpeningQty], ;
PurchaseQty as [PurchaseQty], ;
PurchaseAmount as [PurchaseAmount], ;
OpeningQty + NVL(PurchaseQty,0) as [TotalQty], ;
OpeningAmount + NVL(PurchaseAmount,0) as [TotalAmount], ;
NVL(SoldQty,0) as [SoldQty], ;
NVL(SoldAmount,0) as [SoldAmount], ;
OpeningQty + NVL(PurchaseQty,0) - NVL(SoldQty,0) as [ClosingQty], ;
OpeningAmount + NVL(PurchaseAmount,0) - NVL(SoldAmount,0) as [ClosingAmount] ;
 FROM (select Codes, Products, SUM(qty) as OpeningQty, ;
SUM(Amount) as OpeningAmount from Open_Stock group by Codes, Products) O ;
LEFT JOIN (select Codes, Products, ;
SUM(qty) as PurchaseQty, SUM(Amount) as PurchaseAmount ;
from Purchase group by Codes, Products) P ;
ON O.Codes = P.Codes ;
LEFT JOIN (select Codes, Products, ;
SUM(qty) as SoldQty, SUM(Amount) as SoldAmount ;
from Sales group by Codes, Products) S ;
ON O.Codes = S.Codes

Unfortunately, VFP doesn't allow spaces in field names (it seems). If you can have purchases without having an open stock for the item, we need to use FULL OUTER JOIN instead and modify this query a bit.