> > How on earth would such a "tool" work, in a disconnected > > environment? > > By keeping the environment connected. > A CFX is a dll written in C that can stay resident, keep ODBC > connections opened keep user handles in memory, and handle > time limits. > If the CFX locks a row in the database, CF will not be able > to read that row, even if it does it from another connection. > I suppose it would be the same in Java with JDBC.
But the environment isn't connected. You have no guarantee that the user will make a subsequent request, or when they'll make it, or even that the user hasn't been wiped off the face of the earth by a giant meteor. So, your connection logic will need to deal with that, and by doing this you're turning a fairly simple, reliable solution to concurrency into a complicated, unreliable solution that'll create bottlenecks. The simple, reliable solution to concurrency is to let your application track changes to records. For example, user A requests a record to edit. While user A is staring at his screen, trying to figure out what to change, user B requests the same record to edit. User B finishes quickly, and saves his changes. When user A attempts to save his changes, the application first checks the record to see if it's changed - for example, by comparing a timestamp field's value with the value it contained when user A first requested the record. If the values don't match, user A can't just overwrite user B's changes - how you specifically handle this is up to you. Dave Watts, CTO, Fig Leaf Software http://www.figleaf.com/ Fig Leaf Software provides the highest caliber vendor-authorized instruction at our training centers in Washington DC, Atlanta, Chicago, Baltimore, Northern Virginia, or on-site at your location. Visit http://training.figleaf.com/ for more information! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Introducing the Fusion Authority Quarterly Update. 80 pages of hard-hitting, up-to-date ColdFusion information by your peers, delivered to your door four times a year. http://www.fusionauthority.com/quarterly Archive: http://www.houseoffusion.com/groups/CF-Talk/message.cfm/messageid:252564 Subscription: http://www.houseoffusion.com/groups/CF-Talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=11502.10531.4
