Querying nested documents embedded in compound XML documents

• US 20070244860A1
• Filed: 04/12/2006
• Published: 10/18/2007
• Est. Priority Date: 04/12/2006
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Mineev, Alexandre, Carlson, Jason, Hayes, Christopher
• Granted Patent: US 7,805,424 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/8373 Query execution
• CPC Class Codes: Y10S 707/99931 Database or file accessing

Abstract

Querying a compound XML document having a primary XML document and multiple nested documents may be performed in a single query. The single query comprises an expression of at least one attribute and the encoding type of the nested documents. Execution of the query involves decoding each nested document according to its encoding type and searching for the attribute specified in the query. The results returned from each of the nested documents may be combined with the results returned from the primary document before returning the results to the user.

Claims

1. A method to query a compound XML document, the method comprising:

receiving a compound XML document comprising a primary document and a first nested document;

determining an encoding type associated with the first nested document;

generating a single query against the compound document, the query comprising an attribute and the encoding type of the first nested document;

executing the query and receiving a rowset from the first nested document.

2. The method of claim 1, wherein receiving a compound XML document comprises receiving an XML document with multiple levels of nested documents.

3. The method of claim 1, wherein determining an encoding type associated with the first nested document comprises determining whether the first nested document is encoded as an HTML-encoded document or as a Base64-encoded document.

4. The method of claim 1, wherein generating a single query against the compound document further comprises generating a single query that requests a value of one or more attributes found in both the primary XML document and the first nested document.

5. The method of claim 4, further comprising:

collecting rowsets from the primary document and the first nested document and producing a composite rowset.

6. The method of claim 5, wherein generating a single query against the compound document further comprises a query against a second nested document, wherein the second nested document is contained within the first nested document.

7. The method of claim 5, wherein the single query against the compound document further comprises a query against a plurality of nested documents having a peer encoded document at one or more nested levels.

8. The method of claim 5, wherein executing the query comprises decoding the first nested document associated with a first encoding type to reveal contents of the first nested document and decoding the second nested document associated with a second encoding type to reveal contents of the second nested document and querying the contents of both revealed documents.

9. A computer system to query a compound XML document, the system comprising:

a processing unit to execute a program to query the compound XML document;

a data storage device comprising a program to interpret a single query statement against the compound XML document;

a user interface to input elements of the single query statement and present return results;

wherein the compound XML document comprises a primary XML document and a first encoded nested document and a second encoded nested document, wherein the elements of the single query statement comprise at least one attribute and encoding information for the first and second nested documents, and wherein the processor units acts to execute the single query statement such that the at least one attribute is returned from both the first nested document and second nested document.

10. The system of claim 9, further comprising:

a storage device which accumulates results from the first encoded nested document and the second encoded nested document and combines the results into a composite query return from the compound XML document.

11. The system of claim 9, wherein the encoding of the first encoded nested document and the second encoded nested document is at least one of HTML and Base64.

12. The system of claim 9, wherein the single query further comprise at least one attribute from the primary XML document and wherein results from the primary XML document are returned with results from the first and second encoded nested documents.

13. The system of claim 9, wherein the second encoded nested document is contained within the first encoded nested document.

14. The system of claim 9, wherein the processor units acts to execute the single query statement such that the at least one attribute is returned from both the first nested document and second nested document by using the encoding information to decode the first and second nested documents in order to expose contents of each before assessing the at least one attribute.

15. A computer-readable medium having computer-executable instructions for performing a method of querying against a compound XML document, the method comprising:

receiving a compound XML document comprising a primary document and a first nested document;

determining an encoding type associated with the first nested document;

generating a single query against the compound document, the query comprising an attribute and the encoding type of the first nested document;

executing the query and receiving a rowset from the first nested document; and

providing composite results of the first nested document.

16. The computer-readable medium of claim 15, wherein the step of determining an encoding type used in the nested document comprises determining whether the first nested document is encoded as an HTML-encoded document or as a Base64-encoded document.

17. The computer-readable medium of claim 15, wherein the step of generating a single query against the compound document further comprises generating a single query that requests a value of the attribute found in both the primary XML document and the first nested document.

18. The computer-readable medium of claim 15, wherein the step of generating a single query against the compound document further comprises a query against a second nested document, and wherein the second nested document is contained within the first nested document.

19. The computer-readable medium of claim 18, wherein the first nested document has a first encoding type and the second nested document has a second encoding type.

20. The computer-readable medium of claim 19, wherein the step of executing the query comprises decoding the first nested document associated with the first encoding type to reveal contents of the first nested document and decoding the second nested document associated with the second encoding type to reveal contents of the second nested document and querying the contents of both revealed documents.