Updating and maintaining data in a multi-system network using asynchronous message transfer

• US 7,383,289 B2
• Filed: 12/02/2003
• Issued: 06/03/2008
• Est. Priority Date: 12/02/2003
• Status: Active Grant

• Current Assignee: SAP SE
• Original Assignee: SAP AG (SAP SE)
• Inventors: Kraft, Frank Michael
• Primary Examiner(s): LEWIS, CHERYL RENEA
• Application Number:
  US10/726,295
• Publication Number:
  US 20050120061A1
• Time in Patent Office: 1,645 Days
• Field of Search: 707/8, 707/104.1, 707200-203, 707/10, 707103 R-103 Z
• US Class Current: 1/1
• CPC Class Codes: G06F 16/24552 Database cache management
• CPC Class Codes: G06F 16/27 Replication, distribution or synchronisation of data between databases or within a distributed database system; Distributed database system architectures therefor
• CPC Class Codes: G06F 16/275 Synchronous replication

Abstract

Techniques are provided for updating a local cache database of an application system in a multi-system environment having a central system that maintains central data objects that are shared by the multiple systems. A first application system executes an application and processes a document using a data object having a version identifier. A message is sent to a second application system including the data object used to process the document and a corresponding version identifier for the data object. The second application system receives the message, and the version identifier in the message is compared to a version identifier of a corresponding data object stored in the second application system. If the version identifier of the data object stored in the second application system indicates that a more recent version of the data object exists, the more recent version of the data object is requested from a central system that maintains the data objects and the second system is updated.

Claims

1. A method of updating a local cache of an application system in a multiple-system environment having a central system that maintains central data objects that are shared by the multiple systems, the method comprising:

receiving a message from a first application system, the message identifying a data object having a version identifier assigned by the central system;

comparing the version identifier of the data object in the message to a version identifier of a corresponding data object stored in the local cache of a second application system;

requesting, from the central system, a more recent copy of the data object in the central system if the version identifier of the data object stored in the local cache of the second application system indicates that a more recent version of the data object exists; and

updating the local cache of the second application system with the more recent copy of the data object in the central system.

2. The method of claim 1 wherein the version identifier is a timestamp that indicates the time of the modification of the data object.

3. The method of claim 1 wherein the version identifier is a version number that is incremented after each modification of the data object.

4. The method of claim 1 wherein the message from the first application system contains the data object having a version identifier assigned by the central system.

5. The method of claim 1 wherein the message from the first application system identifies a document that was processed using the data object.

6. The method of claim 1 wherein the updating of the local cache database of the second application system with a most recent copy of the data objects is performed by receiving an asynchronous message from the central system containing a most recent copy of the data objects.

7. The method of claim 1 wherein the central data objects are shared by the multiple systems by storing a copy of the central data objects in a local cache of each system.

8. The method of claim 7 wherein the central system updates the local cache of each system by sending an asynchronous message to each system containing the most recent copy of the central data objects.

9. A method of updating a local cache of an application system in a multiple-system environment having a central system that maintains central data objects that arc shared by the multiple systems, the method comprising:

executing an application in a first application system and processing a document using a data object having a version identifier assigned by the central system;

sending a message to a second application system containing a data object identifier to identify the data object used to process the document and the version identifier that corresponds to the data object;

receiving the message at the second application system and comparing the version identifier of the data object in the message to a version identifier of a corresponding data object stored in the local cache of the second application system;

requesting, from the central system, a more recent copy of the data object in the central system if the version identifier of the data object stored in the local cache of the second application system indicates that a more recent version of the data object exists; and

updating the local cache of the second application system with the more recent copy of the data object in the central system.

10. The method of claim 9 wherein the version identifier is a timestamp that indicates the time of the modification of the data object.

11. The method of claim 9 wherein the version identifier is a version number that is incremented after each modification of the data object.

12. The method of claim 9 wherein the message identifies the document that was processed using the data object.

13. A computer readable medium having embedded thereon executable instructions that when executed cause a processor of an application system in a multiple-system environment having a central system that maintains central data objects that are shared by the multiple systems to:

in response to receiving a message from a system, the message identifying data objects having version identifiers assigned by the central system, compare the version identifiers of the data objects in the message to version identifiers of corresponding data objects stored in the local cache of the application system;

request, from the central system, a most recent copy of the data objects in the central system if the version identifiers of the data objects stored in the local cache of the application system indicate that a more recent version of the data objects exist; and

update the local cache of the application system with the most recent copy of the data objects in the central system.

14. The method of claim 13 wherein the version identifier is a timestamp that indicates the time of the modification of the data object.

15. The method of claim 13 wherein the version identifier is a version number that is incremented after each modification of the data object.

16. The method of claim 13 wherein the message contains the data object having a version identifier assigned by the central system.

17. The method of claim 13 wherein the message identifies a document that was processed using the data object.

18. The method of claim 13 wherein the update of the local cache of the application system with a most recent copy of the data objects is performed by receiving an asynchronous message from the central system containing a most recent copy of the data objects.

19. The method of claim 13 wherein the central data objects are shared by the multiple systems by storing a copy of the central data objects in a local cache of each system.

20. The method of claim 19 wherein the central system updates the local cache of each system by sending an asynchronous message to each system containing the most recent copy of the central data objects.