Querying and fragment extraction within resources in a hierarchical repository

• US 20080147614A1
• Filed: 12/18/2006
• Published: 06/19/2008
• Est. Priority Date: 12/18/2006
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Baby, Thomas, Agarwal, Nipun, Tam, Man-Hay
• Granted Patent: US 7,840,590 B2
• Time in Patent Office: Days
• US Class Current: 707/3
• CPC Class Codes: G06F 16/8373 Query execution

Abstract

Techniques for efficiently processing a query are provided. A query may specify a location path and a content path. The location path identifies the hierarchical location of a set of documents within a resource repository. The content path identifies hierarchical location of one or more nodes within the content of the set of documents. Computing the query includes using a repository index, based on the location path and the content path, to generate first results corresponding to the set of documents and second results corresponding to the one or more nodes. Final results of the query are based on the first results and second results. Another technique is provided for formatting a locator value in the repository index to support data that is stored object-relationally. Another technique is provided for storing index information about virtual content.

Claims

1. A machine-implemented method, comprising:

receiving a query that includes;

a location path that identifies the hierarchical location of a set of documents within a resource repository, and

a content path that identifies hierarchical location of one or more nodes within the content of the set of documents;

computing the query, wherein computing includes;

using, based on the location path, an index to generate first results corresponding to the set of documents, and

using, based on the content path, said index to generate second results corresponding to the one or more nodes; and

computing results of the query based on the first results and the second results;

wherein said index includes entries that;

index the hierarchical location of each resource of a plurality of resources in the resource repository, and

index nodes within the content of each resource of the plurality of resources.

2. The method of claim 1, wherein the content of a resource includes at least one of the following:

system properties of the resource, user-defined properties of the resource, and the data of the resource.

3. The method of claim 2, wherein:

the content includes system properties of the resource; and

the system properties of each resource in the resource repository conform to a particular XML schema.

4. The method of claim 2, wherein:

the content includes user-defined properties of the resource; and

a subset of the user-defined properties do not conform to a particular XML schema.

5. The method of claim 2, wherein:

the content includes the data of the resource; and

a subset of the data does not conform to a particular XML schema.

6. The method of claim 1, wherein:

the index comprises a path identifier column and a locator column; and

a bit in the locator column of an index entry indicates whether the corresponding path identifier indicates a location path of the resource that corresponds to said index entry or an XPath string of a node, in the resource, that corresponds to said index entry.

7. The method of claim 1, wherein:

said location path specifies a location of a first set resources in said resource repository;

said content path includes an XPath string that identifies content in a second set of resources in said resource repository; and

said index is used to lookup said location path and said XPath string.

8. The method of claim 1, wherein a subset of said plurality of resources is stored outside of said resource repository when said index is generated.

9. The method of claim 1, wherein:

each resource is associated with one or more properties; and

at least one of said one or more properties is stored on disk as one datatype and resides in memory as a different datatype.

10. The method of claim 1, wherein:

a first subset of said plurality of resources are stored in an object-relational (O-R) format,

a second subset of said plurality of resources are stored in a large object (LOB) format, and

the index includes a locator column that is used as both a locator of resources in O-R format and a locator of resources in LOB format.

11. The method of claim 10, wherein the LOB format includes at least one of the following formats:

text within a character large object (CLOB) and encoded binary XML in a binary large object (BLOB).

12. The method of claim 10, wherein:

the query specifies an XPath string that indicates a fragment is to be extracted;

the fragment is a portion of a particular resource of said plurality of resources;

the particular resource is an XML document conforming to an XML schema;

the index is used to determine a locator value, corresponding to the locator column, of one or more nodes specified by the XPath string; and

the locator value is used to extract the fragment from where the particular resource is stored.

16. A machine-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 1.

17. A machine-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 2.

18. A machine-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 3.

19. A machine-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 4.

20. A machine-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 5.

21. A machine-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 6.

22. A machine-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 7.

23. A machine-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 8.

24. A machine-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 9.

25. A machine-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 10.

26. A machine-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 11.

27. A machine-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 12.

13. A machine-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform computing a query that, when executed, causes an index to be accessed, wherein:

the index indexes a plurality of resources in a hierarchical repository,

a first subset of the plurality of resources are stored in an object-relational (O-R) format,

a second subset of the plurality of resources are stored in a Large Object (LOB) format, and

the index includes a locator column that is used as both a locator of resources in O-R format and a locator of resources in LOB format.

14. The machine-readable medium of claim 13, wherein the LOB format includes at least one of the following formats:

text within a character large object (CLOB) and encoded binary XML in a binary large object (BLOB).

15. The machine-readable medium of claim 13, wherein:

the query specifies an XPath string that indicates a fragment to be extracted;

the fragment is of a particular resource in said resource repository;

the particular resource is an XML document conforming to an XML schema;

the index is used to determine a locator value, corresponding to the locator column, of one or more nodes specified by the XPath string; and

the locator value is used to extract the fragment from where the particular resource is stored.