I have done a little with XPath over the years, but I've never spent that much time learning it in any detail. Since we have added XPath 1.0 support I'd thought I would site back and and learn a bit more about it.
For an excellent Tutorial that covers all of the basics of node discovery it is best to first read:
If you only read one tutorial, this is the one to read. It will get you through all of the basics of finding nodes and searching in deeply nested XML documents. I particularly liked this tutorial since the author had went through a lot of trouble to visually explain the results of XPath queries.
Another Tutorial to look at is:
I thought the examples were poor, but is has a very clear explanation of terminology used in XPath. What I am finding is that using the built in Xpath with fulltext works quite well.
What would be an improvement? Finding someone to contribute an XML fulltext parser plugin. Getting an index around the XML would make it quite a bit more useful...