Few other systems have filtering implemented as comprehensively as NAV, nor do they have it tied so neatly to the detailed retention of historical data. The result of NAV's features is that even the most basic implementation of NAV includes very powerful data analysis capabilities available to the end user.

As developers, we should appreciate the fact that we cannot anticipate every need of any user, let alone anticipate all the needs of all the users. We know we should give the users as much freedom as possible to allow them to selectively extract and review data from their system. Wherever feasible, users should be given the opportunity to apply their own filters so that they can determine the optimum selection of data for their particular situation. On the other hand, freedom, here as everywhere, is a double-edged sword. With the freedom to decide just how to segment one's data, comes the responsibility for figuring out what constitutes a good segmentation to address the problem...