Changing the content of an XML document

[Piewald, Georg]

> Wolfgang [mailto:http://x-query.com/mailman/listinfo/talk] wrote:
> 
> > 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)?

Actually I can reduce my question to the following: Assuming I have a
variable which stores a node-tree like that

let $tree :=
  <node>
    <subnode>
      some text
    </subnode>
  </node>

In reality $tree is the entire XML file which I want to send back to the
client. Now, depending on some conditions I want to change the content
of <subnode> "some text" to "some other text", before sending it. I
don't actually want to alter the file in the database, just the message
that I'm sending.

If I placed the XML-file inside the script, I would write something like

<node>
  <subnode>
  {
    if ($condition)
    then "some text"
    else "some other text"
  }
  </subnode>
</node>

But since I have a couple of not too small XML files I fear that this
will get a bit overcrwoded.
Do you understand what I mean?

Best,
Georg