Maintaining Semantics in the Design of Valid and Reversible SemiStructured Views

Existing systems that support semistructured views do not maintain semantics during the process of designing views. Thus, there is no guarantee that the views obtained are valid and reversible views. In this paper, we propose an approach to designing valid and reversible semistructured views. We employ four types of view operators, namely, select, drop, join and swap operators, and develop a set of rules to maintain the semantics of the views when the swap operator is applied. We also examine the reversible view problem and develop rules to guarantee the designed views are reversible. Finally, we examine the possible changes to the participation constraints of relationship types and propose rules to keep the participation constraints correct.