replacing nodes and sub-trees

Hi,

I have an table where I use XML data type to store documents. The following is an example of original document:

<!ORIGINAL DOCUMENT>

<ABC>

<xyz>.....</xyz>

<xyz>.....</xyz>

<gef>.....</gef>

<qew>....</qew>

</ABC>

<!NEW DOCUMENT>

<ABC>

<xyz>.....</xyz>

<gef>.....</gef>

<reb>....</reb>

</ABC>

My question is how to update the original document so that the two previous instances of xyz tag are replaced by the new single xyz tag, the original gef tag is replaced by the new gef tag, and the reb tag is added to the original document as it is not not present in the original document. The qew will not be updated. I can do this using DOM but I am looking to accomplish this using xquery and xml dml. Is this possible ? I appreciate help on this.

Thanks

It sounds like your algorithm is

For each element name in the NEW document, delete all the elements of that name in the OLD document and insert the new element into the OLD document.

You could do this w/ XQuery DML by generating a DML statement based on the NEW document.