This thesis presents the implementation of a knowledge base system for rough sets [Paw92]within the logic programming framework. The combination of rough set theory with logic programming is a novel approach. The presented implementation serves as a prototype system for the ideas presented in [VDM03a, VDM03b]. The system is available at "http://www.ida.liu.se/rkbs". The presented language for describing knowledge in the rough knowledge base caters for implicit definition of rough sets by combining different regions (e.g.

The social community is structured around data, a lot of that data is stored in different types of databases. The meaning of this essay is to develop an interactive tool that will change the way database visualization is done, and also to research in which fields a tool of this type can be used. With the help of different methods we discovered areas where it could be of use, such as; presentation of a database, development and documentation of a database. The primary goal of the prototype was to make viewing of database structures easier, even people without prior database knowledge should be able to understand the structure. During the development we used prototypes.