Changing the content of an XML document

[Wolfgang]

> This means, in the script I load the XML file into a
> local variable using the doc() function and return the result to the
> client.
 >
 > But now, occationally some of the content of the file has to be altered.

I'm not sure I completely understand the question. Is the document 
stored in the db or do you load it from the filesystem? And do you only 
need to temporarily change some content of that file (in which case I 
would probably call an XSLT) or permanently (use XQuery update extensions)?

Wolfgang