[Q] Help finding info on desgining disconnected DB systems?

First, this is cross-posted to comp.databases.theory, comp.databases.informix & comp.soft-sys.powerbuilder as I really need to get some assistance. I hope the cross-posting doesn't offend. I'm looking for info that relates to designing, implementing & "best methods" for a disconnected system....i.e., an off-line & on-line system. Since today's market is mostly client-server apps I'm having difficulty finding books and other info relating to the better methods of implementing this type of system. For example: How to maintain & update serial fields between off-line & on-line systems? Best way to handle modifications (modify & delete) of records between users that can access any of the data? One user may delete a record on his copy (PC) of a record while another user has made a modification to their copy. What happens to the on-line copy when the record is "deleted" before the "modified" version is posted against the on-line DB. If it helps, the off-line (PC) system is being developed in Powerbuilder 4.0 using the Watcom DB & the on-line (Unix) system is using Informix 5.x. Thanks in advance. ===================================== | Ms. Terry Lee Hyattsville, MD USA | | tmlee@access.digex.net :-) | =====================================