Automatic data synchronization between a handheld and a host computer using pseudo cache including tags and logical data elements

An integrated information system, comprising:

• a host computer comprising:
• a data set including logical data elements of a user database;
• and
• a handheld computer adapted to communicate with the host computer comprising:
• a processor;
• a common data set which is a shared version of the host computer data set, the common data set including the logical elements of the user database;
• a communication port coupled to said processor, said communication port adapted to link said processor with the host computer;
• and
• a data synchronization engine coupled to said processor and said communication port, said data synchronization engine including:
• one or more tags, each of said tags corresponding to one of the logical data elements in the user database, each of said tags including at least a modified flag;
• and
• a pseudo cache engine coupled to the processor that maintains the states of each said tags responsive to changes to corresponding ones of the logical data elements in the user database;
• wherein said data synchronization engine initiates a synchronization of a logical data element with the host computer over the communication port when an associated one of the tags is modified in the pseudo cache.

A method for communicating data records between a handheld computer and a host computer, the handheld computer and host computer each having at least one common data set including logical data elements of a user database, each computer having copies of the common data set, the method comprising the steps of:

• providing a pseudo cache having tag entries in the handheld computer corresponding to the logical data elements;
• establishing a communication link between the handheld computer and the host computer in response to a change of a pseudo cache tag entry;
• synchronizing data records stored by the handheld computer and the host computer, said synchronizing steps including:
• searching tag entries of the pseudo cache for shared data records;
• and
• modifying one or more o the tag entries coupled to said pseudo cache;
• resolving any differences in the copies and storing identical copies of the common data set in the host computer and in the handheld computer.

A desktop computer adapted to communicate with a handheld computer, the handheld computer having a data set including logical data elements in user database, the desktop computer comprising:

• a processor;
• a common data set which is a shared version of the handheld computer data set including the logical elements of the user database;
• a communication port coupled to said processor, said communication port adapted to link said processor with the handheld computer;
• and
• a data synchronization engine coupled to said processor and said communication port, said data synchronization engine including:
• one or more tags each corresponding to one of the logical data elements in the user database;
• wherein said data synchronization engine receives a synchronization of a logical data element within the host computer over the communication port when an associated one of the tags is written to a pseudo cache engine in the handheld computer with a set modified bit, the pseudo cache engine in the handheld computer maintaining the states of the associated ones of the tags in the handheld computer responses to changes to corresponding ones of the logical data elements in the user database in the handheld computer, and
• wherein the synchronization of a logical data element reflects a change in the state of an associated one of the tags in the handheld computer.