Pavel Loupal

XCase - a tool for conceptual XML data modeling

Conceptual modeling of XML data was made easier with the introduction of the XSEM model, which utilizes the MDA (Model-driven architecture) ideas of multi-level modeling. XCase is an implementation of this model, enabling users to model their problem domain as a Platform-independent model (PIM), from which Platform-specific models (PSM), XML schemas in our case, can be derived. The main advantage of this approach is maintainability of multiple XML schemas describing the same data from different views as XCase maintains connections between PIM and PSM levels, so that in case of a change to some element, this change can be propagated to all the places where this element is used.

The XML-λ XPath Processor: Benchmarking and Results

This paper presents XML-λ, our approach to XML processing based on the simply typed λ-calculus. A λ-calculus model of both the XML and XPath languages is described and a prototype implementation is investigated. We benchmark the prototype implementation, comparing it to existing XPath processors -- Apache Xalan, Saxon, and Suns Java JAXP. Surprisingly, although the prototype is more of an idea validation tool than a benchmark tuned software, XPath query evaluation is fast, especially on pre-loaded XML documents. Benchmark results support our decision to use XML-λ as an XML database data storage model. This work is part of a long-term effort targeted at designing a native XML database management system built upon this theoretical model.