Tip of the Month (April 2001)

Synchronizing a Single Handheld to Two Desktop Machines

You might want to synchronize your Visual CE table to two computers. For example, you may want to synchronize it to a computer at home and a computer at work. You can do this, but you will have to set the "custom" synchronization options as follows:

Desktop	Action	Handheld
does not exist	copy to desktop	new/changed
new	copy to handheld	does not exist
still exists	copy to handheld	deleted
still exists	update desktop	changed
still exists	update desktop	unchanged
deleted	copy to desktop	unchanged

This will work pretty well, but you will have these two problems:

• If you delete a record it might "reappear" unless you delete it from all three machines
  
  
• Records changed on the desktop will not find their way to the handheld (changes on the handheld will find their way to the desktop).

If you are using timestamp synchronization:

Desktop	Action	Handheld
does not exist	copy to desktop	new/changed
new	copy to handheld	does not exist
unchanged	delete from desktop	deleted
unchanged	update desktop	changed
changed	update handheld	unchanged
deleted	copy to desktop	unchanged
changed	copy to handheld	deleted
changed	ask user	changed

This will work pretty well, but you will have these two problems:

• If you delete a record it might "reappear" unless you delete it from all three machines
  
  
• After we synchronize a record, we mark it (internally) as "unchanged" on the handheld. Say you change a record (either on the desktop A or the handheld) and synchronize the handheld to desktop A. Then (without changing the record on the handheld or desktop B), you synchronize to desktop B. Since the record was not marked as changed on the handheld or desktop B, it will not be copied to desktop B.