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 -  This project is free software; you can redistribute it and/or modify it
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 -  This program is distributed in the hope that it will be useful, but
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-->
<Sales xmlns:sql="urn:schemas-openlink-com:xml-sql">
    <sql:sqlx><![CDATA[  
	select  XMLELEMENT ('Month', 
             XMLATTRIBUTES (sub.year as "year", sub.month as "month"),
                (select XMLAGG (        
                         XMLELEMENT ('Category', XMLATTRIBUTES (sub2.CategoryName), XMLELEMENT ('Sales', sub2.volume)) 
                       )
                      from 
                        (select
                         cat.CategoryName as CategoryName, 
                         sum (od.Quantity*od.UnitPrice*(1-od.Discount)) as volume 
                         from Demo.demo.Orders o1, Demo.demo.Order_Details od, Demo.demo.Products p, Demo.demo.Categories cat 
                         where od.OrderID = o1.OrderID and od.ProductID = p.ProductID and cat.CategoryID = p.CategoryID 
                         and year(o1.OrderDate) = sub.year and month(o1.OrderDate) = sub.month
                         group by 1 
                        ) sub2
                   )
          )
        as result from 
        (select distinct year(o.OrderDate) as year, 
                month(o.OrderDate) as month from Demo.demo.Orders o) sub
	]]></sql:sqlx>
</Sales>
