Ontology-Driven Keyword Search for Heterogeneous XML Data Sources

Massive heterogeneous XML data sources emerge on the Internet nowadays. These data sources are generally autonomous and provide search interfaces of XML query language such as XPath or XQuery. Accordingly, users need to learn complex syntaxes and know the schemas. Keyword Search is a user-friendly information discovery technique, which can assist users in obtaining useful information conveniently without knowing the schemas, and is very helpful to search heterogeneous XML data. In this chapter, the authors present a system called SKeyword which provides a common keyword search interface for heterogeneous XML data sources, and employs OWL ontology to represent the global model of various data sources. Section 1 introduces the context of keyword search for heterogeneous XML data source. In Section 2, the preliminary knowledge is given, and the semantics of keyword search result in ontology is defined. In section 3, the system architecture is described. Section 4 presents the approaches of ontology integration and index building used by SKeyword. Section 5 presents the generation algorithm of searching results and discusses how to rewrite the keyword search of global conceptual model to into the XQuery sentences for local XML sources. Section 6 discussed how to organize and rank the results. Section 7 shows the experiments. Section 8 is the related work. Section 9 is the conclusion of this chapter.