Application Of Active Database Technology In Virtual Reality

This paper introduce the active database system and ECA active rules. And then it define a series of active rules in virtual reality system.There are five chapters in this paper. The first chapter of the paper introduces the background of the project and actuality of this area. It also introduces the basic conception of active database system and virtual reality system. The second chapter of the paper introduces the structure of active database system and the active database Program Language. It also introduces the Oracle database system and its mechanism of constraint and trigger at the end of this chapter. The third chapter of the paper introduces Knowledge Model and the Execute Model of the active database system. In addition, it expounds event, condition, action and their Transaction Model. The forth chapter of the paper introduces a series of active rules used in virtual reality system. There are two parts in these active rules. One is consistency, constraint and trigger scripts in database system, such as PL/SQL scripts in Oracle. The Other is codes in virtual reality system, such as VRML with active function in virtual reality. In this part, it puts forward the requirement of virtual reality system for active rules. And then it brings forward the design target and frame thinking. At last it summarizes material functional model, a section of codes and flow chart of active rules. The last chapter of the paper is conclusion and future work about the active rule.