Technique for creating a unique quasi-random row identifier

• US 6,363,389 B1
• Filed: 05/28/1999
• Issued: 03/26/2002
• Est. Priority Date: 09/24/1998
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Yothers, Jay A., Lyle, Robert William
• Primary Examiner(s): Breene, John
• Assistant Examiner(s): LEWIS, CHERYL RENEA
• Application Number:
  US09/322,286
• Time in Patent Office: 1,033 Days
• Field of Search: 707/10, 707/101, 707/1, 707/2, 707/3, 707/4, 707/5, 707/6, 707/9, 707/100, 709/201
• US Class Current: 707/695
• CPC Class Codes: G06F 16/284 Relational databases
• CPC Class Codes: Y10S 707/968 Partitioning
• CPC Class Codes: Y10S 707/99931 Database or file accessing
• CPC Class Codes: Y10S 707/99932 Access augmentation or optimizing
• CPC Class Codes: Y10S 707/99933 Query processing, i.e. searching
• CPC Class Codes: Y10S 707/99934 Query formulation, input preparation, or translation
• CPC Class Codes: Y10S 707/99935 Query augmenting and refining, e.g. inexact access
• CPC Class Codes: Y10S 707/99936 Pattern matching access
• CPC Class Codes: Y10S 707/99939 Privileged access

Abstract

The present invention discloses a method, apparatus, and article of manufacture for generating a row identification number within a computer. In accordance with the present invention, the row identification number is associated with a row in a database. The database is stored on a data storage device connected to a computer. A unique row identification number is created by using a computer-dependent timestamp. The unique row identification number is manipulated so that the row identification number is quasi-random.

Claims

1. A method of generating a row identification number within a computer, the row identification number being associated with a row in a database, wherein the database is stored on a data storage device connected to the computer, the method comprises:

creating a unique row identification number by using a computer-dependent timestamp; and

manipulating the unique row identification number so that the row identification number is quasi-random.

2. The method of claim 1, wherein the computer-dependent timestamp comprises a plurality of bits having an order and wherein manipulating the unique row identification number further comprises:

reversing the order of a portion of the bits; and

locating the reversed portion of the bits in front of a remaining portion of the bits.

3. The method of claim 1, wherein the method further comprises:

receiving computer dependent information; and

appending the computer-dependent information to the computer-dependent timestamp to create the unique row identification number.

4. The method of claim 3, wherein the computer-dependent timestamp is located in front of the computer-dependent information.

5. The method of claim 3, wherein the computer-dependent information comprises a central processing unit identification number.

6. The method of claim 3, wherein the computer-dependent information comprises a machine-type number.

7. The method of claim 3, wherein the computer-dependent information comprises a version code.

8. The method of claim 3, wherein the computer is connected to a plurality of computers, and wherein each computer has rows having row identification numbers, and wherein each row identification number is unique among the plurality of computers.

9. The method of claim 1, wherein the method further comprises using the row identification number as a database partitioning key in a partitioned database.

10. The method of claim 1, wherein the method further comprises using the computer-dependent timestamp contained within the row identification number to determine a time at which a particular row was inserted into the database.

11. An apparatus for generating a row identification number within a computer, the row identification number being associated with a row in a database, comprising:

a computer having a data storage device connected thereto, wherein the data storage device stores the database; and

one or more computer programs, performed by the computer, for creating a unique row identification number by using a computer-dependent timestamp, and manipulating the unique row identification number so that the row identification number is quasi-random.

12. The apparatus of claim 11, wherein the computer-dependent timestamp comprises a plurality of bits having an order and wherein the means for manipulating further comprises one or more computer programs, performed by the computer, for reversing the order of a portion of the bits, and locating the reversed portion of the bits in front of a remaining portion of the bits.

13. The apparatus of claim 11, further comprising one or more computer programs, performed by the computer, for receiving computer dependent information, and appending the computer-dependent information to the computer-dependent timestamp to create the unique row identification number.

14. The apparatus of claim 13, wherein the computer-dependent timestamp is located in front of the computer-dependent information.

15. The apparatus of claim 13, wherein the computer-dependent information comprises a central processing unit identification number.

16. The apparatus of claim 13, wherein the computer-dependent information comprises a machine-type number.

17. The apparatus of claim 13, wherein the computer-dependent information comprises a version code.

18. The apparatus of claim 13, wherein the computer is connected to a plurality of computers, and wherein each computer has rows having row identification numbers, and wherein each row identification number is unique among the plurality of computers.

19. The apparatus of claim 11, further comprising one or more computer programs, performed by the computer, for using the row identification number as a database partitioning key in a partitioned database.

20. The apparatus of claim 11, further comprising one or more computer programs, performed by the computer, for using the computer-dependent timestamp contained within the row identification number to determine a time at which a particular row was inserted into the database.

21. An article of manufacture comprising a computer program carrier readable by a computer and embodying one or more instructions executable by the computer to perform a method that generates a row identification number within a computer, the row identification number being associated with a row in a database, wherein the database is stored on a data storage device connected to the computer, the method comprises:

creating a unique row identification number by using a computer-dependent timestamp; and

manipulating the unique row identification number so that the row identification number is quasi-random.

22. The article of manufacture of claim 21, wherein the computer-dependent timestamp comprises a plurality of bits having an order and wherein manipulating the unique row identification number further comprises:

reversing the order of a portion of the bits; and

locating the reversed portion of the bits in front of a remaining portion of the bits.

23. The article of manufacture of claim 21, wherein the method further comprises:

receiving computer dependent information; and

appending the computer-dependent information to the computer-dependent timestamp to create the unique row identification number.

24. The article of manufacture of claim 23, wherein the computer-dependent timestamp is located in front of the computer-dependent information.

25. The article of manufacture of claim 23, wherein the computer-dependent information comprises a central processing unit identification number.

26. The article of manufacture of claim 23, wherein the computer-dependent information comprises a machine-type number.

27. The article of manufacture of claim 23, wherein the computer-dependent information comprises a version code.

28. The article of manufacture of claim 23, wherein the computer is connected to a plurality of computers, and wherein each computer has rows having row identification numbers, and wherein each row identification number is unique among the plurality of computers.

29. The article of manufacture of claim 21, wherein the method further comprises using the row identification number as a database partitioning key in a partitioned database.

30. The article of manufacture of claim 21, wherein the method further comprises using the computer-dependent timestamp contained within the row identification number to determine a time at which a particular row was inserted into the database.