System for Accessing a Relational Database Using Semantic Queries

• US 20150269223A1
• Filed: 03/20/2014
• Published: 09/24/2015
• Est. Priority Date: 10/22/2010
• Status: Active Grant

• Current Assignee: Data.World, Inc.
• Original Assignee: Daniel P. Miranker, Juan F. Sequeda
• Inventors: Miranker, Daniel Paul, Sequeda, Juan Federico
• Granted Patent: US 9,396,283 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/25 Integrating or interfacing systems involving database management systems
• CPC Class Codes: G06F 16/353 into predefined classes
• CPC Class Codes: G06F 16/81 Indexing, e.g. XML tags; Data structures therefor; Storage structures
• CPC Class Codes: G06F 16/8358 Query translation
• CPC Class Codes: G06F 16/8365 Query optimisation
• CPC Class Codes: G06F 16/86 Mapping to a database
• CPC Class Codes: G06F 16/90332 Natural language query formulation or dialogue systems

Abstract

This invention is a system for integrating relational databases into a semantic web framework utilizing a simple mapping process and the SQL query optimizer present in the SQL database engine.

Claims

1. A system comprised of one or more computers for executing a digitally encoded database query received by the system, said query being expressed in a semantic query language, on the contents of a relational database with a corresponding relational database schema, said system comprising:

A module adapted to automatically translate the received database query into a second digitally encoded database query expressed in a relational query language by using a subset of the contents of a mapping data structure representing a mapping from the pre-existing relational database schema to a synthetic domain model that is a putative ontology automatically created from the relational schema, in order to create a translated relational query; and

A module that is adapted to execute the translated query on the relational database, said execution module being operatively connected to the query translation module.

2. The system of claim 1 further comprising a module that is adapted to optimize the translated query prior to its execution by the database module.

3. The system of claim 2 where the optimization module is further adapted to detect unsatisfiable conditions.

4. The system of claim 2 where the optimization module is further adapted to execute a self-join elimination.

5. The system of claim 2 where the optimization module is further adapted to execute a self outer join elimination.

6. The system of claim 1 where the generating module is further adapted to use a synthetic domain model expressed in OWL.

7. The system of claim 1 where the generating module is further adapted to use a synthetic domain model expressed in RDFS.

8. The system of claim 1 further comprising a module adapted to create from the mapping an RDF logical representation of the relational database data that conforms to the synthetic domain model.

9. The system of claim 1 further comprising a module adapted to create an RDF logical representation using a view definition associated with the relational database.

10. The system of claim 9 where the view definition is a SQL view definition.

11. The system of claim 9 where the view definition is logical.

12. The system of claim 9 where the view definition is materialized.

13. The system of claim 10 where the body of the SQL view definition is nested in the translated query.

14. The system of claim 1 where the translating module is further adapted to output a relational query where the arguments of the relational query are the columns of the RDF logical representation of the relational database data contents.

15. The system of claim 1 where the translating module is further adapted to convert a URI into a string comprised of a combination of a table name identifying a data table and a column label associated with the identified table.

16. The system of claim 1 where the database module is further adapted to have materialized the database contents as an RDF representation.

17. The system of claim 1 where the translation module is further adapted to determine component substitutions of at least one of the components comprising the received query.

18. The system of claim 1 further comprising a second translation module that translates the result of the translated relational query into a query result that conforms to the semantic query language.