On Tuesday, September 20, 2011 5:42:32 PM UTC-4, nick name wrote: > > I need to have a number that generally increases with every request made to > the service. The only requirement is that it is strictly monotonous - I > don't need a specific start, and I don't care if there are any holes. > > Possible solutions: > > - Insert a record into a dummy table, and use the last-row-id of the dummy > record. Occasionally, (e.g. in a batch job) delete every record except the > last. (Or maybe including the last? do all dbs supported maintain a sequence > counter independent of the current maximum value of a column?) >
How are you going to use that number to determine which records have changed since last sync -- are you going to store it with each record in the table? If that's the plan, rather than creating a dummy table and keep adding records to it, can't the dummy table just include a single row (with a single field, besides id) containing the current count -- then just update that single record on every request (or more appropriately, every time there's an insert/update to the DB you're syncing)? Anthony
