ECAI-2002 Conference Paper

[full paper]

Querying semistructured data using a rule-oriented XML query language

Tadeusz Pankowski

The goal of the paper is to propose a semistructured data model for representing XML documents and a language for querying semistructured database representing XML data. The language is based on a path calculus and its extension involving rules (in Datalog style) and Skolem functions. Two kinds of matching between query variables and database objects are discussed: a rigid and a flexible matching. The flexible matching is of special importance since the XML data does not conform to a rigid schema, its structure is often not known in advance and its structure may change frequently. We propose a method, based on path expressions with forward and backward elongations, supporting valuations of query variables according to a rigid or a flexible matching. The containment problem for this two matchings is discussed. The main idea of an experimental implementation is outlined.

Keywords: information retrieval, knowledge representation

Citation: Tadeusz Pankowski: Querying semistructured data using a rule-oriented XML query language. In F. van Harmelen (ed.): ECAI2002, Proceedings of the 15th European Conference on Artificial Intelligence, IOS Press, Amsterdam, 2002, pp.302-306.