xslt key and match

Question

I am pretty new to xslt, sorry for the confusion i caused and may waste your time... Actually what I am really trying to do is: I have two queries, first query (orders/order)

<query name="orders" rowElementName="order">
 select ordernumber, subtotal, total
 from tablex
</query>

return something like:

ordernumber subtotal total
123 20 23.5
234 19 26.5

another query (orderitems/lineitem)

<query name="OrderItems" rowElementName="lineitem">
 select ordernumber, cartitemid, productname, sku
 from tabley
</query>

return something like:

ordernumber cartitemid productname sku
123 3 test1 s9sdidk
123 4 test2 s9sdidl
234 5 test3 s9sdidu
234 6 test4 s9sdidh

and then output like this (seperate two orders):

Product sku

---

test1 s9sdidk
test2 s9sdidl

---

     Subtotal:  20.00    
     Total: 23.5 

Product sku

---

test3 s9sdidu
test4 s9sdidh

---

     Subtotal:  19.00    
     Total: 26.5