Updating data in a multi-system network that utilizes asynchronous message transfer

• US 20060004806A1
• Filed: 06/01/2004
• Published: 01/05/2006
• Est. Priority Date: 06/01/2004
• Status: Abandoned Application

• Current Assignee: SAP AG (SAP SE)
• Original Assignee: SAP AG (SAP SE)
• Inventors: Kraft, Frank Michael
• Application Number:
  US10/858,221
• Publication Number:
  US 20060004806A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/273 Asynchronous replication or reconciliation

Abstract

Techniques are provided for updating a locally stored version of a data set in a multiple-system environment where each system maintains a separate stored version of the data set and is capable of modifying the data set. A data set stored locally in a first application system is modified and a message is generated containing a modification value and the first application system'"'"'s modified data set. The message is sent to a second application system that also maintains a version of the data set. The second application system compares its locally-stored data set to the data set of the message. Based on the results of the comparison, the second application system either replaces a data value in its locally-stored data set with a data value in the message or adds the modification value in the message to the data value in its data set.

Claims

1. A method of updating a locally stored version of a data set, wherein multiple application systems each maintain a separate stored version of the data set and are each capable of modifying the data set, wherein the data set comprises a data value and a change value for each of the multiple application systems that indicates the most recent modification from the respective application system that has been reflected in the data value, the method comprising:

receiving, from a first application system of the multiple application systems and at a second application system of the multiple application systems, a message containing

     1) the data set as locally stored in the first application system, and

     2) a modification value that indicates a modification made to the data set as locally stored in the first application system; and

for each change value in the received message, comparing the change value of the data set stored locally in the second application system with the corresponding change value in the received message; and

if the comparison indicates that the change value for the first application system in the message is more recent than the corresponding change value in the data set of the second application system and that the change values for all other application systems in the message are equal to the change values for the corresponding application systems in the data set of the second application system, then replacing the data value in the data set of the second application system with the data value in the received message; and

if otherwise, then adding the modification in the message to the data value in the data set of the second application system.

2. The method of claim 1 further comprising comparing the replaced data value in the data set of the second application system with the data value that would result from the addition of the modification in the message to the data value in the data set of the second application system before replacing the data value in the data set of the second application system with the data value in the message.

3. The method of claim 2 further comprising correcting the data set of the second application system if the replaced data value in the data set of the second application system is not equal to the result of the addition of the modification in the message to the data value in the data set of the second application system before replacing the data value in the data set of the second application system with the data value in the message.

4. The method of claim 2 further comprising indicating to the multiple application systems that the data set of the second application system contains an error if the replaced data value in the data set of the second application system is not equal to the result of the addition of the modification in the message to the data value in the data set of the second application system before replacing the data value in the data set of the second application system with the data value in the message.

5. The method of claim 1 wherein the first application system sends messages to the second application system after each modification of the data set of the first application system.

6. The method of claim 5 wherein the first application system uses asynchronous message transfer to send the messages to the second application system.

7. The method of claim 1 wherein the change value is a timestamp that indicates the time of the modification to the data set.

8. The method of claim 1 wherein the change value is a version number that is incremented after each modification to the data set.

9. A method of updating a locally stored version of a data set, wherein multiple application systems each maintain a separate stored version of the data set and are each capable of modifying the data set, wherein the data set comprises a data value and a change value for each of the multiple application systems that indicates the most recent modification from the respective application system that has been reflected in the data value, the method comprising:

modifying the data value of a data set stored locally in a first application system;

generating a message containing the modification to the data set of the first application system and the modified data set as locally stored in the first application system; and

sending the message to a second application system that maintains a version of the data set.

10. The method of claim 9 wherein the first application system generates the message and uses asynchronous message transfer to send the message to the second system.

11. The method of claim 9 wherein the first application system sends a message to the second application system containing the modification to the data set of the first application system and the modified data set as locally stored in the first application system after each modification to the data set of the first application system.

12. The method of claim 9 wherein the change value is a timestamp that indicates the time of the modification of the data set of the first application system.

13. In a multiple system environment wherein each of the multiple application systems maintain a separate stored version of a data set and are each capable of modifying the data set, the data set comprising a data value and a change value for each of the multiple application systems that indicates the most recent modification from the respective application system that has been reflected in the data value, a computer program product tangibly embodied on an information carrier comprising executable instructions that when executed cause a receiving application system in the multiple-system environment to:

receive, from a sending application system, a message containing

     1) the data set as locally stored in the sending application system, and

     2) a modification value that indicates a modification made to the data set as locally stored in the sending application system; and

for each change value in the received message, compare the change value of the data set stored locally in the receiving application system with the corresponding change value in the received message; and

if the comparison indicates that the change value for the sending application system in the message is more recent than the corresponding change value in the data set of the receiving application system and that the change values for all other application systems in the message are equal to the change values for the corresponding application systems in the data set of the receiving application system, then replace the data value in the data set of the receiving application system with the data value in the received message; and

if otherwise, then add the modification in the message to the data value in data set of the receiving application system.

14. The computer program product of claim 13 further causing the receiving application system to compare the replaced data value in the data set of the receiving application system with the data value that would result from the addition of the modification in the message to the data value in the data set of the receiving application system before replacing the data value in the data set of the receiving application system with the data value in the message.

15. The computer program product of claim 14 further causing the receiving application system to correct the data set of the receiving application system if the replaced data value in the data set of the receiving application system is not equal to the result of the addition of the modification in the message to the data value in the data set of the receiving application system before replacing the data value in the data set of the receiving application system with the data value in the message.

16. The computer program product of claim 14 further causing the receiving application system to indicate to the multiple application systems that the data set of the receiving application system contains an error if the replaced data value in the data set of the receiving application system is not equal to the result of the addition of the modification in the message to the data value in the data set of the receiving application system before replacing the data value in the data set of the receiving application system with the data value in the message.

17. The computer program product of claim 13 wherein the sending application system sends messages to the receiving application system after each modification of the data set of the sending application system.

18. The computer program product of claim 13 wherein the sending application system uses asynchronous message transfer to send the messages to the receiving application system.

19. The computer program product of claim 13 wherein the change value is a timestamp that indicates the time of the modification to the data set.

20. The computer program product of claim 13 wherein the change value is a version number that is incremented after each modification to the data set.