title: how to know if data has changed
body: <p>If you have a desktop application on different clients which use the same database how do you notify the other clients if one client has changed data. Say if you as a client number 1 is looking at a datagrid with different customers and client number 2 updates a name on one of the customers you are looking at in the datagrid. How do client number 1 become aware of the change from the database? I do not think the solution would be to pull every second to the server. So what would be the choice? </p>