Abstract: A mobile terminal and an anti-theft method thereof are described. The anti-theft recognition module of the mobile terminal sends a security number acquisition instruction to a security number acquisition module after determining that the mobile terminal enters an anti-theft mode, the security number acquisition module automatically acquires a security number according to the security number acquisition instruction and sends the acquired security number to an anti-theft processing module, the anti-theft processing module gives an alarm according to the received security number to help the owner of the mobile terminal retrieve the mobile terminal or the information stored in the mobile terminal, thereby minimizing the loss of the owner of the mobile terminal and eliminating the potential safety hazard brought by the loss of the personal information stored in the mobile terminal.

Abstract: The present invention provides a method for searching a change log item, which includes: in a change log of a data synchronizing device, ordering change log items according to numerical values of entity identifiers contained in the items; in the data synchronizing device, when data updating occurs in an entity in a database of the data synchronizing device, using a search algorithm of elements in an ordered sequence to search out whether a change log item containing an entity identifier of the entity exists in the change log. The present invention also provides a data synchronizing device.

Abstract: A method and device for maintaining a changelog in data synchronization are provided in the present invention, in which the changelog is configured to record an operation executed for an object and is composed of data record items. The data record item includes flag information configured to uniquely identify an object and an operation type corresponding to the flag information, the operation type includes adding, updating and deleting. The method includes: reading, between two times of the data synchronization, flag information of a first data record item which is required to be added to the changelog; searching for whether there is a second data record item including the flag information in the changelog, and in a situation that there is the second data record item, setting the second data record item according to the first data record item. By the present invention, the changelog file can be prevented from continuously increasing.