Temporal Dependencies
نویسنده
چکیده
Static integrity constraints involve only the current database state. Temporal integrity constraints involve current, past, and future database states; they can be expressed by essentially unrestricted sentences in temporal logic. Certain syntactically restricted classes of temporal constraints have been studied in their own right for considerations of feasibility or practicality; they are usually called temporal dependencies. Most temporal dependencies proposed in the literature are dynamic versions of static functional dependencies.
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