Technical Report Number
Computing Milleux, Software, Computer Applications, Computer Systems Organization
In a multilevel security database there are multiple beliefs about a given real world object. The ability of a database model to accommodate multiple beliefs is termed polyinstantiation in the multilevel security literature. In this paper we remark that in an abstract sense polyinstantiation is a priori present in all models for temporal and spatial databases. In particular we investigate the applicability of the parametric model for temporal data to query multilevel security data and, as a case study, compare it to a model for multilevel security given by Winslett, Smith, and Qian.