Abstract
Various temporal functional dependencies have already been proposed by different researches in the field. The basic idea of these dependencies is to extend the functional dependency by including a time state. It is only the reflection of static relationship among attributes. This paper presents a new dynamic dependency. We give the concept of the stability constraint and established complete axioms for stability constraints. Generalization is an important abstract semantics. In this paper, the relationship between the class and the subclass is regarded as a scheme constraint. We present the concept of the inheritance dependency and show that the inference rules for inheritance dependencies are correct and complete. In this paper, we set up a series of design methods for temporal databases based on the generalization semantics and the stability constraint. The theory of the inheritance dependency and the stability constraint provide the guarantee for the semantic unanimity of the class hierarchy.
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