Update Document problem

Question

Hi,
I am trying to update an existing document in a container using a query, and being more specific i want to add a new node in the document. I've tried to do it using XmlModify :
try {
     XmlUpdateContext updateContext = mgr.createUpdateContext();
               // query for all the documents that we want to update
XmlResults results = mgr.query(txn, fullQuery, context, null);
XmlValue value = results.next();
while (value != null) {
     XmlDocument document = value.asDocument();
XmlModify mod = mgr.createModify();
String Violation="Violation";
XmlQueryExpression select =mgr.prepare("collection('myData.dbxml')/QoSdb/QoEViolation", context);
mod.addAppendStep(select, XmlModify.Element, "MyChild", "This is my child");
mod.execute(results, context, updateContext);
value = results.next();
          } catch (XmlException e) {
but it wasn't successful..
Any suggestions on how to do this?
I am using the latest release of Berkeley XML DB, and i am working on Fedora OS
Thanks in advance
Panayiotis

Answer 1

Hi,
There are at least a couple of things wrong:
1. Your select (XmlQueryExpression) needs to be a query that is relative to the context of the XmlModify.execute() call, which is a document (or whatever is returned by the "fullQuery" expression (you didn't include that). Typically, this means that the XQuery expression for the select query starts with "." or "/" and not "collection()"
2. you call mod.execute(results, ...) and not mod.execute(value, ...)
This is done after calling results.next(), which means that your context is not what I think you want it to be.
Regards,
George