N. Bassiliades, I. Vlahavas, “Intelligent Querying of Web Documents Using a Deductive XML Repository”, Proc. 2nd Hellenic Conference on AI (SETN '02), I. Vlahavas, C. Spyrolpoulos (Ed.), Springer-Verlag, LNAI 2308, pp. 437-448, 2002.
In this paper, we present a deductive object-oriented database system, called X DEVICE, which is used as a repository for XML documents. X DEVICE employs a powerful rule-based query language for intelligently querying stored Web documents and data and publishing the results. XML documents are stored into the OODB by automatically mapping the DTD to an object schema. XML elements are treated either as objects or attributes based on their complexity, without loosing the relative order of elements in the original document. The rule-based language features second-order logic syntax, generalized path and ordering expressions, which greatly facilitate the querying of recursive, tree-structured XML data and the construction of XML trees as query results. All the extended features of the rule language are translated through the use of object metadata into a set of first-order deductive rules that are efficiently executed against the object database using the system’s basic inference engine.