From the Repository Type list, select between Memory and File to specify where the message identifiers will be stored before the deduplication process. For this scenario, select File.
In the File store field, specify the location of the file storing message identifiers.
In the Expression field, enter an expression to filter the messages. In this scenario, enter the following expression to filter the messages according to the person node of the XML files: xpath("/people/person"), and leave all the other parameters as they are. Alternatively, you can select the Use language check box, select XPath from the Language list, and enter "/people/person" in the Predicate field.