The ICS-FORTH RDFSuite: Managing Voluminous RDF Description Bases

ABSTRACT Metadata are widely used in order to fully exploit information resources available on corporate intranets or the Internet. The Resource Description Framework (RDF) aims at facilitating the creation and exchange of metadata as any other Web data. The growing number of available information resources and the proliferation of description services in various user communities, lead nowadays to large volumes of RDF metadata. Managing such RDF resource descriptions and schemas with existing low-level APIs and le-based implementations does not ensure fast deployment and easy maintenance of real-scale RDF applications. In this paper, we advocate the use of database technology to support declarative access, as well as, logical and physical independence for voluminous RDF description bases. We present RDFSuite, a suite of tools for RDF validation, storage and querying. Speci cally, we introduce a formal data model for RDF description bases created using multiple schemas. Next, we present the design of a persistent RDF Store (RSSDB) for loading resource descriptions in an ORDBMS by exploring the available RDF schema knowledge. Our approach preserves the exibility of RDF in rening schemas and/or enriching descriptions at any time, whilst it outperforms, both in storage volumes and query execution time, other approaches using a monolithic table to represent resource descriptions and schemas under the form of triples. Last, we brie y present RQL, a declarative language for querying both RDF descriptions and schemas, and sketch query evaluation on top of RSSDB. This work was partially supported by the EC project CWeb (IST-1999-13479) and Mesmuses (IST-2000-26074).