Past-directed Evaluation of Dynamic Integrity Constraints in Temporal Databases
نویسندگان
چکیده
This work can be considered a step to simplify the dynamic integrity constraint checking. We propose a method to transform a dynamic constraint to an equivalent past-directed form. This transformation will facilitate the constraint checking in temporal databases. The method proposed deals with integrity constraints defined by first-order logic formulas with explicit time in a denial form. It is based on the construction of time graphs to represent the temporal sequence of states presented in the constraint formula.
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