Hi, I have a problem similar to this:

First xml file is a list of books:

books.xml:

<books>
<book id="1" ......
<book id="2" ......
<book id="3" ......
</ books>

Id is unique (xsd takes care of it)

And for every bookstore (files bookstore_1.xml , bookstore_2.xml ....) I have got xml file with...