Abstract: Disclosed is an improved approach to represent RDF data in a database system, where one or more auxiliary tables are maintained for the RDF data. The auxiliary tables advantageously permit a database processing system to process a query using fewer numbers of joins or self-joins.

Abstract: Systems and methods for visualizing relational data as RDF graphs in order to explore connections between data in the relational schema. The relational data is first converted into an initial RDF graph. Referential constraints between tables in the relational data, including unasserted referential constraints and pseudo-referential constraints, are automatically detected and used to augment the RDF graph. In addition, datatype properties in the RDF graph may be folded into annotation objects for better visualization. The resulting graph may be an edge-node graph, with edges corresponding to referential constraints between nodes corresponding to relational table rows.

Abstract: A method, system, and computer program product for accessing a SPARQL endpoint that is specified from within a SQL database query language statement. A method embodiment receives a SQL database query language statement that is then parsed in order to identify the locations of one or more SPARQL endpoints to be accessed. The database query language statement comprises operations and/or queries (e.g., SPARQL queries) to be performed over at least some linked data (e.g., queries over named RDF graphs) found at the one or more SPARQL endpoints. The database query language statement can also specify relational operations such as a relational database table operation, and/or a view operation, and/or other relational database functions that operate in conjunction with retrieved linked data.