I am new to XSL. I have the following Input XML.

<books>
   <book>
      <author>John Smith</author>
      <name>Introduction to XML</name>
      <address>123 Elm St.</address>
      <phone>(123) 456-7890</phone>
   </book>
   <book>
      <author>John Smith</author>
      <name>Introduction to XSL</name>
      <address>456 Oak Ave.</address>
      <phone>(156) 789-0123</phone>
   </book>
   <book>
      <author>Mike</author>
      <name>Introduction to XSLT</name>
      <address>456 Oak Ave.</address>
      <phone>(156) 789-0123</phone>
   </book>
</books>

Books need to be grouped by author. In the above example John Smith is the author for two books, so the output xml should look like the following.

<authors>
    <author>
            <name>John Smith</name>
            <book>
                <name>Introduction to XML</name>
                <name>Introduction to XSL</name>
            </book>
        </author>
        <author>
            <name>Mike</name>
            <book>
                <name>Introduction to XSLT</name>
            </book>
        </author>
</authors>.

I really appreciate if you can help me with XSL.

For an introduction to grouping in XSLT, see

http://www.jenitennison.com/xslt/grouping

It gets much easier in XSLT 2.0.



Michael Kay
http://www.saxonica.com/

Thanks a ton Michael, per your suggestion I used Muenchian Method and it worked.

Thanks once again,
--R