Database synchronization

• US 20060149794A1
• Filed: 12/08/2005
• Published: 07/06/2006
• Est. Priority Date: 12/10/2004
• Status: Active Grant

• Current Assignee: Seven Networks LLC (SoftBank Group Corp.)
• Original Assignee: Seven Networks International Oy (SoftBank Group Corp.)
• Inventors: Ylinen, Heikki
• Granted Patent: US 9,298,792 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/273 Asynchronous replication or reconciliation

Abstract

Synchronization of data items between parties A and B. A maintains copies of data items and an A change count and a B change count for each data item The A change count indicates the number of changes made by A, and the B change count indicates the number of changes made by B and known to A. After a synchronization trigger, A sends to B each data item that A has changed, plus the A change count and the B. change count for each sent data item A receives from B each data item that B has changed, plus the A change count and the B change count for each received data item A detects a conflict if the received A change count differs from the maintained A change count.

Claims

1. A method for synchronizing a database between an A party and a B party, wherein the database contains data items to be3 synchronized, the method comprising:

maintaining in the A party a copy of the database and an indication of the latest synchronization event between th3e A party and the B party;

maintaining in the A party an A change count and a B change count in respect of each data item to be synchronized;

wherein the A change count indicates the number of changes made to the data item by the A party, and the B change count indicates the number of changes made to the data item by the B party and known to the A party;

in response to a synchronization trigger

sending from the A party to the B party an indication of each data item that the A party has changed after the latest synchronization event, plus the A change count and the B change count in respect of each sent data item,

receiving at the A party from the B party an indication of each data item that the B party has changed after the latest synchronization event, plus the A change count and the B change count in respect of each received data item;

detecting a conflict if the received A change count differs from the maintained A change count.

2. A method according to claim 1, further comprising resolving said conflict according to a set of predetermined values.

3. A method according to claim 2, wherein the conflict resolving step comprises displaying the maintained data item and received data item in a user interface.

4. A method according to claim 2, wherein the conflict resolving step comprises offering the maintained data item and received data item for user selection via a user interface.

5. A method according to claim 2, wherein the conflict resolving step comprises combining the maintained data item and received data item into a single data item.

6. A method according to claim 1, wherein the step of sending the indication of each changed data comprises sending the changed data item itself.

7. A method according to claim 1, wherein the step of sending the indication of each changed data item by the A party comprises sending an identifier of the changed data item, and sending the changed data item itself is responsive to a separate request from the B party.

8. A method according to claim 1, further comprising connecting the A party and the B party via a mobile communication network.

10. A computer program product executable in a data processor, comprising program instructions for causing the data processor to carry out the method according to claim 1 where the program product is executed in the data processor.

9. An apparatus adapted to operate as an A party in a database synchronization with a B party wherein the database contains data items to be synchronized, the apparatus comprising:

means for maintaining a copy of the database and an indication of the latest synchronization event between the A party and the B party;

means for maintaining an A change count and a B change count in respect of each data item to be synchronized;

wherein the A change count indicates the number of changes made to the data item by the A party, and the B change count indicates the number of changes made to the data item by the B party and known to the A party;

means responsive to a synchronization trigger;

for sending from the A party to the B party an indication for each data item that the A party has changed after the latest synchronization event, plus the A change count and the B change count in respect of each sent data items;

for receiving at the A party from the B party an indication of each data item that the B party has changed after the latest synchronization event, plus the a change count and the B change count in respect of each received data item; and

means for detecting a conflict if the received A change count differs from the maintained A change count.