Method, system, and program product for managing hierarchical structure data items in a database

• US 20040122825A1
• Filed: 12/20/2002
• Published: 06/24/2004
• Est. Priority Date: 12/20/2002
• Status: Abandoned Application

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Pulaski, David A.
• Application Number:
  US10/326,187
• Publication Number:
  US 20040122825A1
• Time in Patent Office: Days
• US Class Current: 707/100
• CPC Class Codes: G06F 16/284 Relational databases
• CPC Class Codes: G06F 16/90344 by using string matching techniques

Abstract

The invention manages hierarchical structure data items in a database by assigning a unique value having a sibling value to each data item. This allows child data items of a selected data item to be identified using a single non-recursive operation in which a logical relationship between the unique value assigned to the selected data item and a unique value assigned to each child data item is determined.

Claims

1. A method of managing hierarchical structure data items in a database comprising:

providing a relational database having hierarchically related data items;

assigning a unique value to each data item, wherein each unique value includes a sibling value; and

identifying all child data items of a selected data item using a single non-recursive operation, wherein the child data items are identified by determining a logical relationship between the unique value assigned to the selected data item and a unique value assigned to each child data item.

2. The method of claim 1, wherein the assigning step includes:

determining a location for a data item in a hierarchical structure; and

assigning the unique value for the data item based on the location.

3. The method of claim 1, further comprising defining a maximum number of levels for the hierarchical structure.

4. The method of claim 1, further comprising defining a maximum number of children for any data item in the hierarchical structure.

5. The method of claim 1, further comprising retrieving a sub-tree of the hierarchical structure using a non-recursive query statement.

6. The method of claim 1, further comprising deleting a sub-tree of the hierarchical structure using a non-recursive delete statement.

7. The method of claim 1, wherein each unique value comprises a unique string.

8. The method of claim 7, wherein the unique string comprises a fixed length string including a sibling string for each level of the hierarchical structure.

9. The method of claim 7, wherein each unique value assigned to a parent data item shares a common substring with all unique values assigned to child data items of the parent data item.

10. The method of claim 1, wherein all sibling values comprise a substring having an identical length.

11. A method of retrieving hierarchical structure data items from a database comprising:

providing a relational database having data items;

generating a unique string for each data item, the unique string including a sibling string;

saving each unique string with an associated data item in the database; and

retrieving all data items below a selected data item using a single non-recursive query based on the unique strings.

12. The method of claim 11, wherein the sibling strings all comprise an identical length.

13. The method of claim 11, wherein the step of retrieving includes searching for a common substring in all unique strings.

14. The method of claim 11, wherein the unique string includes a sibling string for all defined levels of the hierarchical structure.

15. A system for managing hierarchical structure data items in a relational database comprising:

a value system that generates a unique value for each data item, wherein each unique value includes a combination of a sibling value and a parent value; and

a management system that manages the data items in the relational database using the unique values.

16. The system of claim 15, further comprising a database system that manages the relational database.

17. The system of claim 15, further comprising a definition system that defines at least one attribute of the hierarchical structure.

18. A computer program product comprising a computer useable medium having computer readable program code embodied therein for managing hierarchical structure data items in a relational database, the program product comprising:

program code configured to define a unique value for each data item, wherein each unique value includes a combination of a sibling value and a parent value; and

program code configured to manage the data items in the relational database using the unique values.

19. The computer program product of claim 18, further comprising program code configured to manage the relational database.

20. The computer program product of claim 18, further comprising program code configured to define at least one attribute of the hierarchical structure.