This paper reports on user experience with Tioga, a DBMS-centric visualization tool developed at Berkeley. Based on this experience, we have designed Tioga-2 as a direct manipulation system that is more powerful and much easier to program. We present a detailed design of the revised system together with an extensive example of its application. We also give a progress report on a Tioga-2 implementation.

We describe DataSplash, a direct manipulation system for creating semantic zoom visualizations of tabular (relational) data. DataSplash makes contributions in three areas that are key to the construction of such visualizations. First, DataSplash helps users graphically specify the visual appearance of groups of objects. Second, the system helps users visually program the way the appearance of groups of objects changes as users browse the visualization. Third, DataSplash allows users to create groups of graphical links between canvases. These direct manipulation facilities simplify the process of constructing semantic zoom applications, particularly ones that display large data sets.