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 realscale 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. Compared to the current status of the W3C standard, our model relies on a complete set of validation constraints for the core RDF/S (without rei cation) and provides a richer type system including several basic types as well as union types. Next, we present the design of a persistent RDF Store (RSSDB) for loading resource descriptions in an object-relational DBMS by exploring the available RDF schema knowledge. Our approach preserves the exibility of RDF in re ning schemas and/or enriching descriptions at any time, whilst it ensures good performance for storing and querying voluminous RDF descriptions. Last, we brie y present RQL, a declarative language for querying both RDF descriptions and schemas, and sketch query evaluation on top of RSSDB.
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