Preference XPATH:A Query Language for E-Commerce

Abstract

We present a new XML-based search technology that enables users to formulate complex customer or vendor preferences which typically occur within e-commerce applications. Preferences are modeled in a natural way by partial orders. Since our semantics of multi-attribute preferences implements the Pareto-optimality principle Preference XPATH queries avoid both the unwanted “emptyresult”-effect and the flooding-effect with lots of irrelevant query results. If perfect matches are not available best possible alternatives are found instead. We have extended the XML query language XPATH by the capability to formulate preferences as soft selection conditions. As our extensions are fully compatible with the XPATH standard both hard and soft selection conditions become now available to any XML-based e-commerce application. Several e-shopping examples show how easy and elegant it is to transform customer wishes into Preference XPATH queries. Our prototype implementation is smoothly integrated with the XML database system Tamino of Software AG. Moreover we show how Preference XPATH can be used within the XML query language QUILT. It even merges with XML style sheets (XSLT) and the XML pointer language (XPointer). Thus with Preference XPATH powerful personalized search engines and match-making processes for B2C and B2B can be implemented completely inside the XML framework.