METHOD AND SYSTEM FOR IMPLEMENTING EFFICIENT UPDATABLE RELATIONAL VIEWS OVER XML DATA

• US 20120296942A1
• Filed: 05/18/2011
• Published: 11/22/2012
• Est. Priority Date: 05/18/2011
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: ARORA, Vikas, BABY, Thomas, LIU, Zhen Hua, YU, Qin
• Granted Patent: US 9,396,284 B2
• Time in Patent Office: Days
• US Class Current: 707/807
• CPC Class Codes: G06F 16/832 Query formulation
• CPC Class Codes: G06F 16/8358 Query translation

Abstract

Disclosed is a method, system, and program product for providing an efficient mechanism to provide updateable relational views over XML. This will allow application developers to write both queries and updates using a relational (SQL) syntax, even though the underlying data is stored as XML. According to some approaches, this is accomplished by implementing a reverse mapping from the data within the views to the node addresses of the corresponding data in the underlying XML document.

Claims

1. A computer implemented method for implementing an update relational view over XML data, comprising:

generating an updateable relational view, wherein the updateable relational view maps row and columns for XML data; and

using a processor to generate a structure for identifying a node address within the XML data that corresponds to a row value in the updateable relational view, wherein the node address is usable to implement an update operation to a node associated with the row value and the update operation comprises a database query language statement.

2. The method of claim 1 in which the database query language statement comprises a SQL statement.

3. The method of claim 1 in which the structure comprises an index table and the node address is stored within a node address column of the index table.

4. The method of claim 3 in which a row expression expressed with either XPath or XQuery is used to construct the index table.

5. The method of claim 1 in which a predicate within the database query language statement is used to filter the node addresses to perform the update operation.

6. The method of claim 1 in which the update operation corresponds to an update statement or a delete statement in the datable query language statement.

7. The method of claim 1 in which the updateable relational view comprises an XMLTABLE( ) construct.

8. The method of claim 1 in which the node address points to a subtree of elements in the XML data.

9. The method of claim 1 in which a callback or reverse conversion function is used to perform the update operation that corresponds to transient XML values.

10. A computer program product embodied on a computer usable medium, the computer readable medium having stored thereon a sequence of instructions which, when executed by a processor causes the processor to execute a method for implementing an update relational view over XML data, the method comprising:

generating an updateable relational view, wherein the updateable relational view maps row and columns for XML data; and

generating a structure for identifying a node address within the XML data that corresponds to a row value in the updateable relational view, wherein the node address is usable to implement an update operation to a node associated with the row value and the update operation comprises a database query language statement.

11. The computer program product of claim 10 in which the database query language statement comprises a SQL statement.

12. The computer program product of claim 10 in which the structure comprises an index table and the node address is stored within a node address column of the index table.

14. The computer program product of claim 10 in which a predicate within the database query language statement is used to filter the node addresses to perform the update operation.

15. The computer program product of claim 10 in which the update operation corresponds to an update statement or a delete statement in the datable query language statement.

16. The computer program product of claim 10 in which the updateable relational view comprises an XMLTABLE( ) construct.

17. The computer program product of claim 10 in which the node address points to a subtree of elements in the XML data.

18. The computer program product of claim 10 in which a callback or reverse conversion function is used to perform the update operation that corresponds to transient XML values.

13. The computer program product of claim 13 in which a row expression expressed with either XPath or XQuery is used to construct the index table.

19. A computer-based system for implementing an update relational view over XML data, comprising:

a computer processor to execute a set of program code instructions;

a memory to hold the program code instructions, in which the program code instructions comprises program code to generate an updateable relational view, wherein the updateable relational view maps row and columns for XML data and use the processor to generate a structure for identifying a node address within the XML data that corresponds to a row value in the updateable relational view, wherein the node address is usable to implement an update operation to a node associated with the row value and the update operation comprises a database query language statement.

20. The system of claim 19 in which the database query language statement comprises a SQL statement.

21. The system of claim 19 in which the structure comprises an index table and the node address is stored within a node address column of the index table.

22. The system of claim 21 in which a row expression expressed with either XPath or XQuery is used to construct the index table.

23. The system of claim 19 in which a predicate within the database query language statement is used to filter the node addresses to perform the update operation.

24. The system of claim 19 in which the update operation corresponds to an update statement or a delete statement in the datable query language statement.

25. The system of claim 19 in which the updateable relational view comprises an XMLTABLE( ) construct.

26. The system of claim 19 in which the node address points to a subtree of elements in the XML data.

27. The system of claim 19 in which a callback or reverse conversion function is used to perform the update operation that corresponds to transient XML values.

28. A computer implemented method for updating data within an update relational view that is constructed over XML data, comprising:

identifying an updateable relational view for an update operation, wherein the updateable relational view maps row and columns for XML data;

receiving instruction to perform an update operation on data within the updateable relational view, wherein the update operation comprises a database query language statement; and

using a processor to perform the update operation, wherein a reverse lookup is performed of a node address within the XML data to perform the update operation.

29. The method of claim 28 in which the database query language statement comprises a SQL statement.

30. The method of claim 28 in which the reverse lookup is implemented by accessing an index structure that stored node addresses for the values in the updateable relational view.

31. The method of claim 28 in which a predicate within the database query language statement is used to filter the node addresses to perform the update operation.

32. The method of claim 28 in which the update operation corresponds to an update statement or a delete statement in the datable query language statement.

33. The method of claim 28 in which the updateable relational view comprises an XMLTABLE( ) construct.

34. The method of claim 28 in which the node address points to a subtree of elements in the XML data.

35. The method of claim 28 in which a callback or reverse conversion function is used to perform the update operation that corresponds to transient XML values.

36. A computer-based system for updating data within an update relational view that is constructed over XML data, comprising:

a computer processor to execute a set of program code instructions;

a memory to hold the program code instructions, in which the program code instructions comprises program code to identify an updateable relational view for an update operation, wherein the updateable relational view maps row and columns for XML data, receive instruction to perform an update operation on data within the updateable relational view, wherein the update operation comprises a database query language statement, and use the processor to perform the update operation, wherein a reverse lookup is performed of a node address within the XML data to perform the update operation.

37. A computer program product embodied on a computer usable medium, the computer readable medium having stored thereon a sequence of instructions which, when executed by a processor causes the processor to execute a method for updating data within an update relational view that is constructed over XML data, the method comprising:

identifying an updateable relational view for an update operation, wherein the updateable relational view maps row and columns for XML data;

receiving instruction to perform an update operation on data within the updateable relational view, wherein the update operation comprises a database query language statement; and

using a processor perform the update operation, wherein a reverse lookup is performed of a node address within the XML data to perform the update operation.