Techniques for automated generation of queries for querying ontologies

• US 8,140,556 B2
• Filed: 01/20/2009
• Issued: 03/20/2012
• Est. Priority Date: 01/20/2009
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Rao, Aditya Ramamurthy, Prakash, Pravin, Rajesh, Narni, Ghosh, Bhaskar Jyoti, Rangarajan, Keshava, Krishnamurthy, Sudharsan, Srinivasan, Nagaraj
• Primary Examiner(s): Leroux, Etienne
• Application Number:
  US12/356,314
• Publication Number:
  US 20100185643A1
• Time in Patent Office: 1,155 Days
• Field of Search: 707/4, 707/5, 707/759, 717/177
• US Class Current: 707/759
• CPC Class Codes: G06F 16/242 Query formulation

Abstract

Techniques for simplifying querying of ontologies. In one embodiment, one or more queries for querying an ontology are automatically generated in a language suitable for querying the ontology. A user may enter a query in a simple language such as a natural language query. In response, one or more queries capable of querying the ontology are automatically generated in a second language. The automatically generated queries may, for example, be in SPARQL or PL/SQL. The one or more automatically generated queries may then be used to query one or more ontologies.

Claims

1. A method of generating a query for querying an ontology, the method comprising:

receiving a first query in a first language, wherein the first language is a natural language;

checking the first query to determine if the first query complies with a predefined grammar and to determine if the first query comprises one or more terms from a vocabulary used in the ontology;

in response to determining that at least one aspect of the first query does not comply with the predetermined grammar and does not comprise one or more terms from the vocabulary used in the ontology, providing guiding formulation of the first query by providing one or more constraints, wherein the one or more constraints are based upon the predefined grammar and the vocabulary comprising terms used in the ontology, and the predefined grammar is based upon a set of one or more rules;

based on the one or more constraints, constraining the first query to comply with the predetermined grammar and the vocabulary used in the ontology; and

generating, based upon the constrained first query, a second query in a second language, wherein the second query complies with the predetermined grammar and the vocabulary used in the ontology, and wherein the second language is different from the first language and the ontology is capable of being queried using the second query in the second language.

2. The method of claim 1 wherein the first query is a natural language query.

3. The method of claim 1 wherein the second language is a Resource Description Framework (RDF) compliant query language for querying an ontology.

4. The method of claim 3 wherein the second language is SPARQL.

5. The method of claim 1 wherein the second language is PL/SQ.

6. The method of claim 1 further comprising:

executing the one or more queries in the second language against the ontology; and

outputting results obtained from executing the one or more queries in the second language against the ontology.

7. The method of claim 1 wherein receiving the first query comprises:

receiving an initial query; and

determining if the initial query complies with the predefined grammar and comprises one or more terms from the vocabulary.

8. The method of claim 1 wherein generating the one or more queries in the second language comprises:

parsing the first query to identify a set of terms in the first query;

associating a tag with each term in the set of terms;

generating one or more representations based upon the set of terms and tags associated with the terms in the set of terms; and

generating the one or more queries in the second language based upon the one or more representations.

9. The method of claim 8 wherein the one or more representations are in XML format.

10. The method of claim 8 wherein generating the one or more queries in the second language based upon the one or more representations comprises:

using mapping information to map at least one term in the set of terms to a term used in the ontology, the mapping information providing a mapping between terms and their corresponding terms used in the ontology.

11. The method of claim 1 wherein the one or more queries in the second language comprise a main query corresponding to the first query and a set of one or more secondary queries configured to gather information in addition to information requested by the first query.

12. A non-transitory computer-readable storage medium storing a plurality of instructions for controlling a processor to generate a query for querying an ontology, the plurality of instructions comprising:

instructions that cause the processor to receive a first query in a first language, wherein the first language is a natural language;

instructions that cause the processor to check the first query to determine if the first query complies with a predefined grammar and to determine if the first query comprises one or more terms from a vocabulary used in the ontology;

in response to determining that at least one aspect of the first query does not comply with the predetermined grammar and does not comprise one or more terms from the vocabulary used in the ontology, instructions that cause the processor to provide guiding formulation of the first query by providing one or more constraints, wherein the one or more constraints are based upon the predefined grammar and the vocabulary comprising terms used in the ontology, and the predefined grammar is based upon a set of one or more rules;

based on the one or more constraints, instructions that cause the processor to constrain the first query to comply with the predetermined grammar and the vocabulary used in the ontology; and

instructions that cause the processor to generate, based upon the constrained first query, a second query in a second language, wherein the second query complies with the predetermined grammar and the vocabulary used in the ontology, and wherein the second language is different from the first language and the ontology is capable of being queried using the second query in the second language.

13. The non-transitory computer-readable storage medium of claim 12 wherein the second language is a Resource Description Framework (RDF) compliant query language for querying an ontology.

14. The non-transitory computer-readable storage medium of claim 13 wherein the one or more queries in the second language comprise a main query corresponding to the first query and a set of one or more secondary queries configured to gather information in addition to information requested by the first query.

15. The non-transitory computer-readable storage medium of claim 12 wherein the second language is SQL or SPARQL.

16. The non-transitory computer-readable storage medium of claim 12 wherein the plurality of instructions further comprises:

instructions that cause the processor to execute the one or more queries in the second language against the ontology; and

instructions that cause the processor to output results obtained from executing the one or more queries in the second language against the ontology.

17. The non-transitory computer-readable storage medium of claim 12 wherein the instructions that cause the processor to generate the one or more queries in the second language comprise:

instructions that cause the processor to parse the first query to identify a set of terms in the first query;

instructions that cause the processor to associate a tag with each term in the set of terms;

instructions that cause the processor to generate one or more representations based upon the set of terms and tags associated with the terms in the set of terms; and

instructions that cause the processor to generate the one or more queries in the second language based upon the one or more representations.

18. The non-transitory computer-readable storage medium of claim 17 wherein the instructions that cause the processor to processor to generate the one or more queries in the second language based upon the one or more representations comprise:

instructions that cause the processor to use mapping information to map at least one term in the set of terms to a term used in the ontology, the mapping information providing a mapping between terms and their corresponding terms used in the ontology.

19. A system for generating a query for querying an ontology, the system comprising:

a memory configured to store the ontology;

a processor coupled to the memory, wherein the processor is configured to;

receive a first query in a first language, wherein the first language is a natural language;

check the first query to determine if the first query complies with a predefined grammar and to determine if the first query comprises one or more terms from a vocabulary used in the ontology;

in response to determining that at least one aspect of the first query does not comply with the predetermined grammar and does not comprise one or more terms from the vocabulary used in the ontology, provide guiding formulation of the first query by providing one or more constraints, wherein the one or more constraints are based upon the predefined grammar and the vocabulary comprising terms used in the ontology, and the predefined grammar is based upon a set of one or more rules;

based on the one or more constraints, constrain the first query to comply with the predetermined grammar and the vocabulary used in the ontology; and

generate, based upon the constrained first query, a second query in a second language, wherein the second query complies with the predetermined grammar and the vocabulary used in the ontology, and wherein the second language is different from the first language and the ontology is capable of being queried using the second query in the second language.

20. The system of claim 19 wherein the second language is a Resource Description Framework (RDF) compliant query language for querying an ontology.

21. The system of claim 19 wherein the processor is configured to:

parse the first query to identify a set of terms in the first query;

associate a tag with each term in the set of terms;

generate one or more representations based upon the set of terms and tags associated with the terms in the set of terms; and

generate the one or more queries in the second language based upon the one or more representations.