A Delta Format for XML: Identifying Changes in XML Files and Representing the Changes in XML

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.

La Fontaine, Robin. XML Europe (2001). Articles>Information Design>XML

Merging XML Files: A New Approach Providing Intelligent Merge of XML Data Sets  

As XML becomes ubiquitous so the need for powerful tools to manipulate XML data becomes more pressing. Merging XML is particularly tricky, but often necessary to consolidate data feeds from heterogeneous systems, or to synchronize submissions of XML fragments which make up a larger document. An automated mechanism for defining and controlling such merges has been developed and is demonstrated to provide a consistent, adaptable and resilient solution to this problem. Integration into an information pipeline allows limitless customization.

La Fontaine, Robin. DeltaXML.com (2001). Articles>Information Design>XML>Collaboration

A Generalized Grammar for Three-way XML Synchronization

This paper proposes a general synchronization grammar which can describe synchronization rule sets. For example, when handling three input files, we show that changes to elements can be described in terms of just seven possible permutations. Similarly, PCDATA and attribute changes can be described in terms of a fixed set of permutations. Using these permutations a grammar is proposed, allowing precise description of synchronization algorithms and rule sets and providing a testable framework for their implementation. The paper applies the resulting grammar to existing synchronization tools and technologies and shows how the grammar can be applied to provide solutions for specific application areas, including document workflow and translation.

La Fontaine, Robin and Nigel Whitaker. IDEAlliance (2005). Articles>Information Design>Programming>XML