--- Klaus Major <[EMAIL PROTECTED]> wrote: > Hi all, > > although I did not receive a response to my first DB > questions, > I dare to ask another question :-) > > Is it possible to directly "search" in the data of a > db cursor? > Or will on have to use a repeat loop through all the > data in a cursor > to find the desired data? Know what I mean? > > Background: > When the user adds/inserts or updates a record, the > current cursor is > not > "up to date" anymore and one has to create a new one > that reflects > these changes > > And of course it is "good style" to display the SAME > data to the user > after that action > and not the first record of the new cursor. > > > Regards > > Klaus Major >
Hi Klaus, It's a very old problem inherent to the SQL query model with database-independent front-ends: how to ensure that all clients have up-to-date data. And this gets even messier when you're taking transactions into account: changes to the database shouldn't be visible to another user until they have completed and the entire transaction is committed. That's why, in most modern databases, cursors are a 'snapshot' of the records that matched your criteria at the time of query execution. Some databases offer 'live' cursors that will fetch the latest information from the database when you 'move' to a record in the result set. That helps but still leaves you in the cold when you're looking at a record that gets updated by another user while you're idle. Of course, you could use a 'send in x seconds' refresh loop. The way FileMaker Pro and other database-tied front-ends do this, is by pushing update information from the database server to all the clients, based on some sort of publish-subscribe scheme. Jan Schenkel. Quartam Reports & PDF Library for Revolution <http://www.quartam.com> ===== "As we grow older, we grow both wiser and more foolish at the same time." (La Rochefoucauld) _______________________________________________ use-revolution mailing list [email protected] Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-revolution
