Decision support for conceptual database design based on the evidence theory

The aim of this work is to present a database design information system, which integrates two important cornerstones of communication. On the on side, it provides an intelligent dialogue interface for conceptual database design; the interactive behaviour of a design dialogue interface facilitates the communication of consistent design information. On the other side, the design information system serves as design information mediator in human-human communication. Conceptual database design is widely recognized as a complex database application. The formalized meta-model serves as communication context for the application conceptual database design. Therefore, it deserves the main attention in the presented work. Unfortunately, existing database design tools have countless shortcomings. One broad class of these shortcomings arises from the fact that these systems lack the means to actively collaborate with the designer over extended periods of time. This work eliminates this disadvantage. It describes our efforts and future directions to address this problem by tightly coupling the conceptual design process with an explicit designer model. Knowing the plans and beliefs of the designer is the most important prerequisite for a self-adaptable design dialogue system. A design system with a designer-adapted design methodology has been proposed by the author. It is based on an explicit representation of information about the designer and knowledge of the designer. An inductive mechanism, based on the Dempster-Shafer theory of evidence, provides the framework for the calculation designer's belief. It is predicated on information about the individual design process behaviour of a designer. Of designer's belief provides arguments for or against some hypotheses about the next design step. The need for a computer-aided design methodology with graphical notation has been well-motivated with a tremendous effort through the exhaustive presentation of the library application. Nowadays, it is nearly a standard that graphical notations are almost always used for complex conceptual database specifications. This fact requires a theoretical well-founded semantic for such notations. This requirement is justified not only because of the possibility to communicate in a unique way using such notations with a well-founded semantic, but also through the methodological aspects. Design dialogue graph rules especially are well-suited for the communication of inter-module dependencies and consistence. Therefore, the new design-by-units methodology is predicated on a graph grammar approach. The process of conceptual schema design is viewed as the process of achieving a series of goals, in particular the creation of an extended enity-relationship model. Examples of goals in the context of enity-relationship modelling are generate enity type, modify an attribute type, etc.