Dynamic Query: Range search on multi-key data sets. The query is formulated through direct manipulation of graphical widgets such as buttons and sliders, one widget being used for every key. The result of the query is displayed graphically and quickly on the screen. Giving a query, a new query is easily formulated by moving with the mouse the position of a slider. An application of dynamic queries is real-estate database. There are sliders for location, number of bedrooms, price of homes. The user moves these sliders to find appropriate homes. Selected homes are indicated by bright points of light.

Progressive Query: Previous queries and results are saved. Queries and results can bothbe iconic, form-based, diagrammatic and VR.