Synchronizing data shared between two devices independent of any other devices that may also share the data

• US 20030182327A1
• Filed: 03/20/2002
• Published: 09/25/2003
• Est. Priority Date: 03/20/2002
• Status: Active Grant

• Current Assignee: Extended Systems Inc. (SAP SE)
• Original Assignee: Extended Systems Inc. (SAP SE)
• Inventors: Krishnapillai, Senthil, Ramanujam, Srinivasan
• Granted Patent: US 7,346,616 B2
• Time in Patent Office: Days
• US Class Current: 707/204
• CPC Class Codes: G06F 16/273 Asynchronous replication or reconciliation
• CPC Class Codes: Y10S 707/99938 Concurrency, e.g. lock management in shared database
• CPC Class Codes: Y10S 707/99952 Coherency, e.g. same view to multiple users

Abstract

A system and method enabling synchronization of data stored on three or more devices in which synchronization between any two of the devices can be conducted independently of the other device. A method embodying the invention involves identifying a record in a first data store that is associated with a change counter that exceeds a maximum change counter recorded for the first data store and updating a second data store using the identified record.

Claims

1. A method for synchronizing data stores, comprising:

recording a highest of one or more change counters associated with a record or records in a first data store as a maximum change counter;

identifying a record in the first data store that is associated with a change counter that exceeds the maximum change counter; and

updating a record in a second data store according to the identified record.

2. The method of claim 1, further comprising replacing the maximum change counter with the change counter associated with the record identified in the first data store.

6. The method of claim 1, wherein updating comprises updating the first data store using a status associated with the identified record.

12. The medium of claim 1, having further instructions for replacing the maximum change counter with the change counter associated with the record identified in the first data store.

3. A method for synchronizing data stores, comprising:

recording a largest of one or more change counters associated with a record or records in a first data store as a first maximum change counter;

recording a largest of one or more change counters association with a record or records in a second data store as a second maximum change counter;

identifying a record in the first data store that is associated with a change counter that exceeds the first maximum change counter; and

updating a record in the second data store according to the record identified in the first data store;

identifying a record in the second data store that is associated with a change counter that exceeds the second maximum change counter; and

updating the first data store according to the record identified in the second data store.

4. The method of claim 3, further comprising replacing the maximum change counter recorded for the first data store with the change counter associated with the record identified in the first data store and replacing the maximum change counter recorded for the second data store with the change counter associated with the record identified in the second data store.

5. A method for synchronizing data stores, comprising:

recording a largest of one or more change counters associated with records in a first data store as a maximum change counter;

for each record in the first data store, comparing the maximum change counter with a change counter associated with that record;

identifying a record in the first data store that is associated with a change counter that exceeds the maximum change counter; and

updating a record in a second data store according to the identified record.

7. The method of claim 5, wherein records in the first data store are each associated with a status, and wherein identifying comprises identifying records in the first data store associated with change counters exceeding the maximum change counter recorded for the first data store, and wherein updating comprises updating records in the first data store using each identified record and the status associated with that record.

8. The method of claim 7, wherein records in the second data store are each associated with a change counter and a status, the method further comprising updating the status and change counter associated with each record updated in the second data store.

9. A method for synchronizing data stores, comprising:

identifying records in a first data store associated with change counters that exceed a maximum change counter recorded for the first data store;

updating records in a second data store using the identified records from the first data store;

identifying records in the second data store associated with change counters that exceed a maximum change counter recorded for the second data store;

updating records in the first data store using the identified records from the second data store;

updating the maximum change counter recorded for the first data store with the highest change counter associated with the identified records from the first data store; and

updating the maximum change counter recorded for the second data store with the highest change counter associated with the identified records from the second data store.

10. The method of claim 9, wherein the records in the first and second data stores are each associated with a change counter and a status;

and

wherein the act of updating the second data store further comprises updating records in the second data store according to the status associated with each record identified in the first data store; and

wherein the act of updating the first data store further comprises updating records in the first data store according to the status associated with each record identified in the second data store; and

wherein the method further comprises updating the status and change counter associated with each record affected by the acts of updating the first and second data stores.

20. The medium of claim 9, wherein the records in the first and second data stores are each associated with a change counter and a status;

and

wherein the instructions for updating the second data store further comprise instructions for updating records in the second data store according to the status associated with each record identified in the first data store; and

wherein the instructions for updating the first data store further comprise instructions for updating records in the first data store according to the status associated with each record identified in the second data store; and

the medium having further instructions for updating the status and change counter associated with each record affected by the acts of updating the first and second data stores.

11. A computer readable medium having instructions for:

recording a largest of one or more change counters associated with a record or records in a first data store as a maximum change counter;

identifying a record in the first data store that is associated with a change counter that exceeds the maximum change counter; and

updating a record in a second data store according to the identified record.

13. A computer readable medium having instructions for:

recording a largest of one or more change counters associated with a record or records in a first data store as a first maximum change counter;

recording a largest of one or more change counters association with a record or records in a second data store as a second maximum change counter;

identifying a record in the first data store that is associated with a change counter that exceeds the first maximum change counter; and

updating a record in the second data store according to the record identified in the first data store;

identifying a record in the second data store that is associated with a change counter that exceeds the second maximum change counter; and

updating the first data store according to the record identified in the second data store.

14. The medium of claim 13, having further instructions for replacing the maximum change counter recorded for the first data store with the change counter associated with the record identified in the first data store and replacing the maximum change counter recorded for the second data store with the change counter associated with the record identified in the second data store.

15. A computer readable medium having instructions for:

recording a largest of one or more change counters associated with records in a first data store as a maximum change counter;

for each record in the first data store, comparing the maximum change counter a change counter associated with that record;

identifying a record in the first data store that is associated with a change counter that exceeds the maximum change counter; and

updating a record in a second data store according to the identified record.

16. The medium of claim 15, wherein the instructions for updating comprise instructions for updating the first data store using a status associated with the identified record.

17. The medium of claim 15, wherein records in the first data store are each associated with a status, and wherein the instructions for identifying comprise instructions for identifying records in the first data store associated with change counters exceeding the maximum change counter recorded for the first data store, and wherein the instructions for updating comprise instructions for updating records in the first data store using each identified record and the status associated with that record.

18. The medium of claim 17, wherein records in the second data store are each associated with a change counter and a status, the medium having further instructions for updating the status and change counter associated with each record updated in the second data store.

19. A computer readable medium having instructions for:

identifying records in a first data store associated with change counters that exceed a maximum change counter recorded for the first data store;

updating records in a second data store using the identified records from the first data store;

identifying records in the second data store associated with change counters that exceed a maximum change counter recorded for the second data store;

updating records in the first data store using the identified records from the second data store;

updating the maximum change counter recorded for the first data store with the highest change counter associated with the identified records from the first data store; and

updating the maximum change counter recorded for the second data store with the highest change counter associated with the identified records from the second data store.

21. A synchronization system, comprising:

a first adapter operable to manage records in a first data store;

a second adapter operable to manage records in a second data store; and

a synch engine in communication with the first and second adapters, the synch engine operable to;

record a largest of one or more change counters associated with a record or records in the first data store as a maximum change counter;

instruct the first adapter to identify a record in the first data store that is associated with a change counter that exceeds the maximum change counter; and

instruct the second adapter to update a record in the second data store according to the identified record.

22. A synchronization system, comprising:

a first adapter operable to compare a maximum change counter with a change counter associated with a record for each record in a first data store and to identify a record in the first data store that is associated with a change counter that exceeds the maximum change counter; and

a second adapter operable to update a record in a second data store according to the record identified by the first adapter; and

a synch engine in communication with the first and second adapters, the synch engine operable to record a highest of one or more change counters associated with records in the first data store as a maximum change counter.

23. A synchronization system, comprising:

a first adapter operable to manage records in a first data store;

a second adapter operable to manage records in a second data store; and

a synch engine in communication with the first and second adapters, the synch engine operable to;

instruct the first adapter to identify a record in the first data store that has a change counter exceeding a maximum change counter recorded for the first data store;

instruct the second adapter to identify a record in the second data store that has a change counter exceeding a maximum change counter recorded for the second data store;

instruct the first adapter to update the first data store using the records identified in the second data store; and

instruct the second adapter to update the second data store using the records identified in the first data store.

24. The system of claim 23, wherein each record in the first and second data stores is associated with a change counter and a status, and wherein:

the first adapter is further operable to identify records in the first data store by, for each record in the first data store, comparing the maximum change counter recorded for the first data store with the change counter associated with the given record; and

the second adapter is further operable to identify records in the second data store by, for each record in the second data store, comparing the maximum change counter recorded for the second data store with the change counter associated with the given record; and

the synch engine is further operable to instruct the first and second adapters to update the first and second data stores using, in part, the status associated with each identified record.

25. The system of claim 24, wherein the synch engine is further operable to update the maximum change counter recorded for the first data store with a change counter associated with the record identified in the first data store and to update the second maximum change counter with a change counter associated with the record identified in the second data store.

26. The system of claim 24, wherein the first adapter is operable to update the change counters and status associated with the records in the first data store affected when the first adapter updates the first data store, and wherein the second adapter is further operable to update the change counters and status of the records in the second data store affected when the second adapter updates the second data store.

27. A synchronization system, comprising:

a first adapter operable to manage records in a first data store;

a second adapter operable to manage records in a second data store;

a third adapter operable to manage a third data store;

a first synch engine in communication with the first, second, and third adapters, the first synch engine operable to;

instruct the first adapter to identify a record in the first data store that has a change counter exceeding a first maximum change counter;

instruct the second adapter to identify a record in the second data store that has a change counter exceeding a second maximum change counter;

instruct the third adapter to identify a record in the second data store that has a change counter exceeding a third maximum change counter;

instruct the first adapter to update the first data store using the records identified in the second and/or third data stores;

instruct the second adapter to update the second data store using the records identified in the first and/or third data stores; and

instruct the third adapter to update the third data store using the records identified in the first and/or second data stores; and

a second synch engine in communication with the second and third adapters, the second synch engine operable to;

instruct the second adapter to identify a record in the second data store that has a change counter exceeding a maximum change counter recorded for the second data store;

instruct the second adapter to identify a record in the third data store that has a change counter exceeding a maximum change counter recorded for the third data store;

instruct the second adapter to update the second data store using the records identified in the third data store; and

instruct the third adapter to update the third data store using the records identified in the second data store.

28. The system of claim 27, wherein each record in the first, second, and third data stores is associated with a change counter and a status, and wherein:

the first adapter is further operable to identify records in the first data store by, for each record in the first data store, comparing the maximum change counter recorded for the first data store with the change counter associated with the given record; and

the second adapter is further operable to identify records in the second data store by, for each record in the second data store, comparing the maximum change counter recorded for the second data store with the change counter associated with the given record;

the third adapter is further operable to identify records in the third data store by, for each record in the third data store, comparing the maximum change counter recorded for the third data store with the change counter associated with the given record;

the first synch engine is further operable to instruct the first, second, and third adapters to update the first, second, and third data stores using, in part, the status associated with each identified record; and

the second synch engine is further operable to instruct the second and third adapters to update the second and third data stores using, in part, the status associated with each record identified in the second and third data stores.

29. The system of claim 28, wherein:

the first synch engine is further operable to update the maximum change counter recorded for the first data store with a change counter associated with the record identified in the first data store, to update the maximum change counter recorded for the second data store with a change counter associated with the record identified in the second data store, and to update the maximum change counter recorded for the third data store with a change counter associated with the record identified in the third data store; and

the second synch engine is further operable to update the maximum change counter recorded for the second data store with a change counter associated with the record identified in the second data store and to update the maximum change counter recorded for the third data store with a change counter associated with the record identified in the third data store.

30. The system of claim 29, wherein:

the first adapter is operable to update the change counters and status associated with the records in the first data store affected when the first adapter updates the first data store;

the second adapter is further operable to update the change counters and status of the records in the second data store affected when the second adapter updates the second data store; and

the third adapter is further operable to update the change counters and status of the records in the third data store affected when the second adapter updates the second data store.

31. A synchronization system comprising:

a means recording a highest of one or more change counters associated with a record or records in a first data store as a maximum change counter;

a means for identifying a record in the first data store that has a change counter exceeding the maximum change counter; and

a means for updating a second data store according to the record identified in the first data store.

32. A synchronization system, comprising:

a means recording a highest of one or more change counters associated with a record or records in a first data store as a first maximum change counter;

a means recording a highest of one or more change counters associated with a record or records in a second data store as a second maximum change counter;

a means for identifying a record in the first data store that has a change counter exceeding the first maximum change counter;

a means for identifying a record in the second data store that has a change counter exceeding the second maximum change counter;

a means for updating the first data store according to the record identified in the second data store; and

a means for updating the second data store according to the record identified in the first data store.

33. In a synchronization environment, a synch status table for containing one or more entries each having a field or fields identifying, at least indirectly, two data stores to be synchronized and a filed or fields identifying a maximum change counter for each of the identified data stores.

34. A synchronization environment comprising:

a first change log table associated with a first data store, the first change log table capable of containing one or more entries, each entry associated with a record in the first data store, each entry having a change counter field for containing a change counter for the associated record;

a second change log table associated with a second data store, the second change log table capable of containing one or more entries, each entry associated with a record in the second data store, each entry having a change counter field for containing a change counter for the associated record; and

a synch status table capable of containing one or more entries each having a field or fields identifying, at least indirectly, the first and second data stores and a field or fields containing a first maximum change counter for the first data store and a second maximum change counter for the second data store.

35. The environment of claim 34, further comprising programming operable to identifying a change counter associated with a record in the first data store that has a value that exceeds all other change counters associated with other records in the first data store and updating the first maximum change counter in the synch status table entry with the value of the identified change counter.

36. The environment of claim 34, further comprising programming operable to identifying a change counter associated with a record in the second data store that has a value that exceeds all other change counters associated with other records in the second data store and updating the second maximum change counter in the synch status table entry with the value of the identified change counter.

37. In a synchronization environment, a method comprising identifying a change counter associated with a record in a data store that has a value that exceeds all other change counters associated with other records in the data store and recording the value of the identified change counter as a maximum change counter.

38. In a synchronization environment, a method comprising:

identifying a change counter associated with a record in a first data store that has a value that exceeds all other change counters associated with other records in the first data store;

identifying a change counter associated with a record in a second data store that has a value that exceeds all other change counters associated with other records in the second data store;

recording the value of the change counter identified with regard to the first data store as a first maximum change counter; and

recording the value of the change counter identified with regard to the second data store as a second maximum change counter.

39. A shared data environment comprising a first, a second, and a third data store, each data store capable of storing shared data, and programming capable of synchronizing the shared data between any two of the first, second, and third data stores without regard to the remaining data store.

40. A synchronization environment comprising:

a first, a second, and a third data store, each data store capable of storing shared data

a first synch engine operable to synchronize shared data between any two of the first, second, and third data stores without regard to the remaining data store; and

a second synch engine operable to synchronize shared data between any two of the first, second, and third data stores according to any prior synchronizations completed by the first or second synch engine and without regard to the remaining data store.