A Delta Format for XML: Identifying Changes in XML Files and Representing the Changes in XML
http://www.gca.org/papers/xmleurope2001/papers/html/s29-2.html

La Fontaine, Robin
XML Europe
2001

Abstract:

This paper describes how changes to XML documents and data files can be represented in XML and proposes a delta format for XML. Although Canonical XML provides a mechanism for verifying that two XML files or documents are equal, it is more often necessary to determine the differences between two XML documents. Such differences should ideally be represented in XML and this paper describes how such changes can be represented in XML with minimal additional attributes and elements. The paper describes how any changes can be simply represented using this delta format, and how the delta file has the same look and feel as the original files being compared. The paper describes how the delta file can be transformed into HTML for viewing by using a simple XSL style sheet, and by modifying this style sheet changes to particular XML file types can be presented to users in a way that suits their view. In addition, the delta file can be processed by any XML application for other purposes.