Hi all, I wnat to update an XML document in my xml database (Marklogic). I have xml as input and want to replace each node that exists in the target xml. If a node does not exist it would be great if it gets added, but thats maybe another task. My XML in the database: <user> <username>username</username> <firstname>firstname</firstname> <lastname>lastname</lastname> <email>[email protected]</email> <comment>comment</comment> </user> The value of $user_xml: <user> <firstname>new firstname</firstname> <lastname>new lastname</lastname> </user> My function so far: declare function update-user ( $username as xs:string, $user_xml as node()) as empty-sequence() { let $uri := user-uri($username) return for $node in $user_xml/user return xdmp:node-replace(fn:doc($uri)/user/fn:node-name($node), $node) }; First of all I cannot iterate over $user_xml/user. If I try to iterate over $user_xml I get "arg1 is not of type node()" exception. But maybe its the wrong approach anyway? Does anybody maybe have sample code how to do this?