Generating one or more XML documents from a relational database using XPath data model

• US 7,174,327 B2
• Filed: 01/31/2002
• Issued: 02/06/2007
• Est. Priority Date: 12/02/1999
• Status: Expired due to Term

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: International Business Machines Corporation
• Inventors: Xu, Jian, Chow, Jyh-Herng, Cheng, Isaac Kam-Chak, Cheng, Josephine Miu, Pauser, Michael Leon, Chau, Hoang K., Chiu, Suet Mui
• Primary Examiner(s): Gaffin; Jeffrey
• Assistant Examiner(s): Wu; Yicun
• Application Number:
  US10/062,127
• Publication Number:
  US 20030014397A1
• Time in Patent Office: 1,832 Days
• Field of Search: 707 1- 10, 707100-1041, 707/103.R, 707/501.1, 707200-206, 717/100, 717/104, 717/114, 709/223, 709/206
• US Class Current: 1/1
• CPC Class Codes: G06F 16/86 Mapping to a database
• CPC Class Codes: Y10S 707/99931 Database or file accessing
• CPC Class Codes: Y10S 707/99933 Query processing, i.e. searching
• CPC Class Codes: Y10S 707/99934 Query formulation, input preparation, or translation

Abstract

A technique is provided for generating one or more XML documents from a relational database using the XPath data model. Data stored on a data storage device that is connected to a computer is transformed. Initially, a document object model tee is generated using a document access definition, which defines the mapping between an XML tree structure and relational tables. The document object model tree is traversed to obtain information to retrieve relational data. The relational data is mapped to one or more XML documents.

Claims

1. A method transforming data stored on a data storage device that is connected to a computer, the method comprising:

generating a document object model tree using a document access definition, wherein the data access definition defines;

(1) a collection of one or more tables in a relational database management system for storing attributes for an XML document, (2) how data stored in the tables maps to the XML document, (3) a query for mapping the data stored in the tables to the XML document, and (4) a table that will contain the XML document after the XML document is generated;

traversing the document object model tree to obtain information to retrieve relational data from the relational database management system; and

mapping the relational data to one or more XML documents using the document access definition.

2. The method of claim 1, wherein the document access definition defines a mapping between the relational data and one or more XML documents.

3. The method of claim 1, wherein the document object model tree comprises one or more relational database nodes.

4. The method of claim 3, wherein a relational database node comprises an attribute node that maps to a column of a relational database table.

5. The method of claim 3, wherein a relational database node comprises an element node that maps to a column of a relational database table.

6. The method of claim 3, wherein a relational database node comprises a text node that maps to a column of a relational database table.

7. The method of claim 3, wherein the relational database node identifies a relational table into which XML document data is to be stored.

8. The method of claim 3, wherein the relational database node identifies a column in a relational table that contains XML document data to be retrieved.

9. The method of claim 3, wherein the relational database node identifies one or more predicates used to select column data from a relational table to store into one or more XML documents.

10. The method of claim 3, wherein the relational database node identifies a join relationship for joining multiple tables.

11. The method of claim 10, wherein the relational database node identifies a primary and foreign key relationship for the join relationship.

12. The method of claim 1, further comprising generating queries to obtain relational data using the document object model tree.

13. The method of claim 1, wherein the relational data comprises an attribute value to be written to an XML document.

14. The method of claim 1, wherein the relational data comprises element text to be written to an XML document.

15. The method of claim 1, further comprising a stored procedure that receives the document access definition and outputs a table populated with the one or more XML documents.

16. An apparatus for transforming data, comprising:

a computer having a data store coupled thereto, wherein the data store stores data; and

one or more computer programs, performed by the computer, for generating a document object model tree using a document access definition, wherein the data access definition defines;

(1) a collection of one or more tables in a relational database management system for storing attributes for an XML document, (2) how data stared in the tables maps to the XML document, (3) a query for mapping the data stored in the tables to the XML document, and (4) a table that will contain the XML document after the XML document is generated, traversing the document object model tree to obtain information to retrieve relational data from the relational database management system, and mapping the relational data to one or more XML documents using the document access definition.

17. The apparatus of claim 16, wherein the document access definition defines a mapping between the relational data and one or more XML documents.

18. The apparatus of claim 16, wherein the document object model tree comprises one or more relational database nodes.

19. The apparatus of claim 18, wherein a relational database node comprises an attribute node that maps to a column of a relational database table.

20. The apparatus of claim 18, wherein a relational database node comprises an element node that maps to a column of a relational database table.

21. The apparatus of claim 18, wherein a relational database node comprises a text node that maps to a column of a relational database table.

22. The apparatus of claim 18, wherein the relational database node identifies a relational table into which XML document data is to be stored.

23. The apparatus of claim 18, wherein the relational database node identifies a column in a relational table that contains XML document data to be retrieved.

24. The apparatus of claim 18, wherein the relational database node identifies one or more predicates used to select column data from a relational table to store into one or more XML documents.

25. The apparatus of claim 18, wherein the relational database node identifies a join relationship for joining multiple tables.

26. The apparatus of claim 25, wherein the relational database node identifies a primary and foreign key relationship for the join relationship.

27. The apparatus of claim 16, further comprising generating queries to obtain relational data using the document object model tree.

28. The apparatus of claim 16, wherein the relational data comprises an attribute value to be written to an XML document.

29. The apparatus of claim 16, wherein the relational data comprises element text to be written to an XML document.

30. The apparatus of claim 16, further comprising a stored procedure that receives the document access definition and outputs a table populated with the one or more XML documents.

31. An article of manufacture comprising a program storage medium readable by a computer and embodying one or more instructions executable by the computer to perform steps for transforming data in a data store connected to the computer, comprising:

generating a document object model tree using a document access definition, wherein the data access definition defines;

(1) a collection of one or more tables in a relational database management system for storing attributes for an XML document, (2) how data stored in the tables maps to the XML document, (3) a query for mapping the data stored in the tables to the XML document, and (4) a table that will contain the XML document after the XML document is generated;

traversing the document object model tree to obtain information to retrieve relational data from the relational database management system; and

mapping the relational data to one or more XML documents using the document access definition.

32. The article of manufacture of claim 31, wherein the document access definition defines a mapping between the relational data and one or more XML documents.

33. The article of manufacture of claim 31, wherein the document object model tree comprises one or more relational database nodes.

34. The article of manufacture of claim 33, wherein a relational database node comprises an attribute node that maps to a column of a relational database table.

35. The article of manufacture of claim 33, wherein a relational database node comprises an element node that maps to a column of a relational database table.

36. The article of manufacture of claim 33, wherein a relational database node comprises a text node that maps to a column of a relational database table.

37. The article of manufacture of claim 33, wherein the relational database node identifies a relational table into which XML document data is to be stored.

38. The article of manufacture of claim 33, wherein the relational database node identifies a column in a relational table that contains XML document data to be retrieved.

39. The article of manufacture of claim 33, wherein the relational database node identifies one or more predicates used to select column data from a relational table to store into one or more XML documents.

40. The article of manufacture of claim 33, wherein the relational database node identifies a join relationship for joining multiple tables.

41. The article of manufacture of claim 40, wherein the relational database node identifies a primary and foreign key relationship for the join relationship.

42. The article of manufacture of claim 31, further comprising generating queries to obtain relational data using the document object model tree.

43. The article of manufacture of claim 31, wherein the relational data comprises an attribute value to be written to an XML document.

44. The article of manufacture of claim 31, wherein the relational data comprises element text to be written to an XML document.

45. The article of manufacture of claim 31, further comprising a stored procedure that receives the document access definition and outputs a table populated with the one or more XML documents.