Oracle International Corporation

Matthew Steven Perry

Souripriya Das

Jagannathan Srinivasan

Victor Antonio Lopez Villamar

Juan Francisco Garcia Navarro

Aravind Yalamanchi

Zhe Wu

Eugene Inseok Chong

Seema Sundara

Ana Paula Estrada Vargas

Ruben Alejandro Gonzalez Yanez

Daniel Diaz Lopez

Techniques are provided for generating and maintaining Precomputed Result Tables ('PRTs') that are used by a database server to improve performance of SPARQL queries that target an RDF graph set. Each PRT corresponds to a particular pattern, which may be simple-triple, star, or chain. The techniques support the creation of PRTs for chain patterns that contain multiple instances of the same property, and PRTs for star and chain patterns that include reverse properties. Techniques are also described for maintaining such PRTs as Data Manipulation Language (DML) operations make changes to the RDF graph tables that belong to the RDF graph set associated with the PRTs.

Using pattern-based result tables to speed up SPARQL queries on RDF graph sets

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.

Method and system for using auxiliary tables for RDF data stored in a relational database

Embodiments use successive refinement to allow a user to systematically explore the result set of an arbitrary query over RDF, such as a SPARQL query. A user inputs an arbitrary base query and modifies this query by replacing selected variables with values to which each selected variable is bound within the result set of the base query. Embodiments present, via a GUI, variable facets that may be substituted for query variables. Embodiments also present, through a GUI, a query history graph that represents query versions that a user has created. A user may navigate this query history graph to return to previously-created query versions. The GUI also provides information about the facets, including a number of results that would be included in the result set of the query version resulting from substitution of the facet for the associated variable.

Method for faceted visualization of a SPARQL query result set

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.

Integrating linked data with relational data

A method and apparatus for introducing domain-specific data types with associated semantics in an RDF database system using an extensibility framework mechanism. The extensibility framework mechanism allows users to map serialized instance data for a particular user-defined data type to properties of a base data structure associated with the domain-specific data and to map instance data in base data structures to the data's serialized form. The RDF database system may return inferred properties of RDF data stored in domain-specific data types in response to a query on the data. Further, the RDF database system may infer relationships between resources in stored data.

Extensible RDF databases

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.

Method and system for visualizing relational data as RDF graphs with interactive response time

A method, system, and computer program product for normalized ranking of semantic query search results. The method commences by forming a SPARQL query, the SPARQL query specifying a collection of named RDF graphs, then executing the SPARQL query to retrieve matched documents selected from the collection of named RDF graphs. Having retrieved the matches, the method calculates an absolute normalized score for the matched document. The calculation of an absolute normalized score for a second matched document allows for relevance ranking. To enhance the relationship of the computer-calculated score to the relevance (and not solely to occurrence counts) embodiments consider the number of distinct variables selected in the SPARQL query, and also consider the total number of bindings to the aforementioned variables. For comparing from among possibly different sized documents, a further normalization component is implemented by considering the total number of triples found in the document's underlying subgraph.

Growing community of inventors

Brookline, NH, United States of America

Matthew Steven Perry