当底层DB更改时，通知应用程序(c++或Java)的最佳方式是什么?

I'm writing a C++ console application that needs to respond to a change in a specific field of a database table. Though I can keep sending a query to check the field periodically, I'd like to avoid this because multiple instances of this application might be running. I have heard of the Query Notification feature of SQL Server 2005 but it seems that the feature would not avaialbe for my setting (SQL Server 2000). In this case what would be a best way to achieve this functionality?I'm writing a C++ console application that need