XML web page E-Commerce etc.

by looking at the w3C tutorial at
http://www.w3schools.com/xml/xml_tree.asp
i can see that their are parents on down to sibling`s.
Question: can the XML be programed to send each or different children
or sibling`s to a nother document or database to reside at a specific
place from one http link.
Example: would be a form as in shopping cart and after the customer
info is filed out and the purchase http button is clicked apoun, the
customer data could be sent to up to 3 different database`s, if not one.
thank you for your time
James