Accessing Relational Databases As Resource Description Framework Databases

• US 20120102022A1
• Filed: 10/21/2011
• Published: 04/26/2012
• 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 8,719,252 B2
• Time in Patent Office: Days
• US Class Current: 707/713
• CPC Class Codes: G06F 16/2452 Query translation
• CPC Class Codes: G06F 16/258 Data format conversion from or to a database

Abstract

This invention is a system and method 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 method executed by a computer system of executing database queries expressed using a first query language where the first query language corresponds to a first type of data organization, on a second type of data organization by translating the query expressed in the first query language into a query expressed in a second query language that corresponds to the second type of data organization.

2. The method of claim 1 further comprising using a mapping from the first data organization to the second data organization.

3. The method of claim 2 further comprising executing the translated query using a computer program that takes queries as input and returns a subset of data from a larger set of data.

4. The method of claim 3 where the first query language is SPARQL, the first type of data organization is a semantic web representation, the second type of data organization is a relational database and the second query language is SQL and the computer program is a SQL database engine.

13. The methods of claims 1-12 with the additional step of optimizing the transform.

14. The method of claim 13 where the optimization step is comprised of detection of unsatisfiable conditions.

15. The method of claim 13 where the optimization step is comprised of self-join elimination.

16. The method of claim 13 where the optimization step is comprised of self outer join elimination.

17. A system comprised of one or more central processing units operatively connected to computer memory containing program code data that when executed by the one or more central processing unites, causes the one or more central processing unites to execute the methods of any of the claims 1-16.

18. A computer readable medium comprising program data, that when executed, causes one or more central processing units to execute any of the methods of claims 1-16.

5. A method for the execution of SPARQL queries by a computer against the contents of a relational database stored in a computer memory, said method comprising

Creating a mapping of the databases schema to the domain model in a Semantic Web language

Creating a logical representation of the database data contents in a relational representation of RDF, consistent with the domain model representation using a SQL view definition

Translating the SPARQL query into a SQL query, where the arguments of the SQL query are the RDF representation of the relational database data contents

Executing the translated SQL query on a relational database system

6. The method of claim 5 further comprising:

Formatting the out of the SQL query to meet the requirements of the SPARQL query.

7. A method for the execution of SPARQL queries by a computer against the contents of a relational database stored in computer memory, said method comprising

Creating a mapping of the databases schema to the domain model in a Semantic Web language

Materializing in a relational database the database contents as an RDF representation

Translating the SPARQL query into a SQL query, where the arguments of the SQL query are the RDF representation of the relational database data contents

Executing the translated SQL query on a relational database system

8. The method of claim 7 further comprising:

Formatting the out of the SQL query to meet the requirements of the SPARQL query.

9. A method for the execution of SPARQL queries by a computer against the contents of a relational database stored in computer memory, said method comprising

Creating a mapping of the databases schema to the domain model in a Semantic Web language;

Materializing in a relational database the database contents as an RDF representation;

Loading the result into a triple-store RDF database management system.

10. A method for executing a SPARQL query by a computer with a corresponding schema on data organized as a relational database stored in a computer comprising:

Creating a mapping of the relational database to the schema associated with the SPARQL query;

Creating a VIEW construct taking as arguments values derived from the mapping;

Translating the SPARQL query into a SQL query that contains a FROM input parameter comprised of a reference to the VIEW construct.

11. The method of claim 10 where the VIEW construct is logical.

12. The method of claim 10 where the VIEW construct has been materialized.