How to create a xml file from oracle sql query

I want to create xml file from the oracle database
Do you have some information or code to send me?
thanks

If that version of Oracle has no 'native' XML support you can always create a DOM Document and start populating it by inserting elements for every row and every attribute. That should be a generic routine that allows you to create an XML view for every ResultSet that is returned, regardless of the content of the ResultSet.