Method, system, and program product for sequential coordination of external database application events with asynchronous internal database events

• US 20030212789A1
• Filed: 05/09/2002
• Published: 11/13/2003
• Est. Priority Date: 05/09/2002
• Status: Active Grant

• Current Assignee: GlobalFoundries, Inc.
• Original Assignee: International Business Machines Corporation
• Inventors: Lindsay, Bruce G., Hamel, Elizabeth B.
• Granted Patent: US 7,426,559 B2
• Time in Patent Office: Days
• US Class Current: 709/225
• CPC Class Codes: G06F 16/273 Asynchronous replication or reconciliation

Abstract

Database management systems, methods, and program products that exploit time dependent sequential database management system processes to insure presentation of the same data or view to one or a plurality of users through sequencing asynchronous database management operations such as recovery and replication. Sequencing is accomplished through the use of entries in sequential logs, including transaction logs, recovery logs, and other data recovery tools and applications. Uses include managing data migration and data replication.

Claims

1. A method for initiating database management system actions to be taken at a future time, comprising entering said actions in a log, and causing said actions to occur only after all database events logged prior to said database management system actions have been analyzed and processed.

2. The method of claim 1 further where initiating database management system actions to be taken at a future time comprises performing a database management system action relating to a distinguished object, said database management system causing a recognizable event to be recorded in a database recovery log.

3. A method of managing a database management system including a replication system and having at least one database table, a recovery log, and a distinguished database table said method comprising entering data into the recovery log pursuant to a change in a database table in the database management system, said method further comprising inserting data describing a command into said distinguished table, and said replication system taking the action of said command after taking actions in response to preceding entries in the recovery log.

4. The method of claim 3 wherein the first command is a signal stopping the capturing of changes related to a database table.

5. The method of claim 3 wherein a second command is a signal starting capturing changes to a database table.

6. The method of claim 5 wherein the database management system comprises at least two database tables, and the second command is a signal starting application of changes of contents of the first database table into second database table.

7. The method of claim 3 wherein the first command is a signal stopping application of changes to data into the first database table, and a second command is a signal starting application of changes to contents of the first database table into the second database table.

8. The method of claim 7 wherein the first command is a signal stopping capturing of changes to data into the first database table, and the second command is a signal capturing changes into the database table.

9. The method of claim 7 comprising performing an operation relating to any database table between the first command and the second command, and thereafter executing the second command.

10. The method of claim 9 comprising changing the schema or metadata of the database table between the first command and the second command, and thereafter executing the second command.

11. The method of claim 3 comprising taking the action of said command entered in the distinguished database table only after taking actions in response to all preceding entries of the recovery log.

12. The method of claim 3 wherein said command entered in said distinguished database tables also controls the processing of database events in a same transaction as said command.

13. A database management system having at least one database table, a recovery log, and a distinguished database table, said database management system being controlled and configured for entering data into the recovery log pursuant to a change in a database table in the database management system, said method further comprising inserting data describing a command into said distinguished database table, said replication system taking the action of said command after taking actions in response to preceding entries in the recovery log.

14. The database management system of claim 13 wherein the first command is a signal stopping the entry of data into the database table.

15. The database management system of claim 13 wherein the second command is a signal starting copying into a database table.

16. The database management system of claim 15 comprising at least two database tables, and the second command is a signal starting copying of contents of the first database table into second database table.

17. The database management system of claim 13 wherein the first command is a signal stopping copying of data into the first database table, and the second command is a signal starting copying of contents of the first database table into the second database table.

18. The database management system of claim 17 wherein the first command is a signal stopping copying of data into the first database table, and the second command is a signal reiniting copying of data into the database table.

19. The database management system of claim 17, wherein said database management system is configured and controlled for performing an operation on the database table between the first command and the second command, and thereafter executing the second command.

20. The database management system of claim 19, wherein said database management system is configured and controlled for changing the schema or metadata of the database table between the first command and the second command, and thereafter executing the second command.

21. The database management system of claim 13 comprising taking the action of said command entered in the distinguished database table only after taking actions in response to all preceding entries of the recovery log.

22. The database management system of claim 13 wherein said command entered in said distinguished database tables also controls the processing of database events in a same transaction as said command.

23. A program product comprising computer readable program code on one or more media, said program code being capable of controlling and configuring a computer system having one or more computers, and including a replication system, at least one database table, a recovery log, and a distinguished database table, said program product program code being adapted to control and configure said database management system for entering data into the recovery log, and where pursuant to a change in a database table in the database management system, data describing a command is entered into said distinguished database table, and said replication system takes an action of said command after taking actions in response to preceding entries in the recovery log..

24. The program product of claim 23 wherein the first command is a signal stopping the entry of data into the database table.

25. The program product of claim 23 wherein a second command is a signal starting copying into a database table.

26. The program product of claim 25 wherein the system comprises at least two database tables, and the second command is a signal starting copying of contents of the first database table into second database table.

27. The program product of claim 23 wherein the first command is a signal stopping copying of data into the first database table, and the second command is a signal starting copying of contents of the first database table into the second database table.

28. The program product of claim 27 wherein the first command is a signal stopping copying of data into the first database table, and the second command is a signal reiniting copying of data into the database table.

29. The program product of claim 27, wherein the database management system is configured and controlled for performing an operation on the database table between the first command and the second command, and thereafter executing the second command.

30. The program product of claim 29, wherein the database management system is configured and controlled for changing the schema or metadata of the database table between the first command and the second command, and thereafter executing the second command.

31. The program product of claim 23 wherein the database management system comprising take the action of said command entered in the distinguished database table only after taking actions in response to all preceding entries of the recovery log.

32. The program product of claim 23 wherein said command entered in said distinguished database tables also controls the processing of database events in a same transaction as said command.