Transitive closure is one of the most important operations in deductive database systems. The author presents the algorithm 2-PBFRTC which computes the fully restricted transitive closure of a database relation with the help of heuristics. In the performance evaluation of 2-PBFRTC it is established that the incorporation of heuristics produces drastic improvement over the use of no heuristics. The algorithm N-PBFRTC is outlined as a generalization of 2-PBFRTC. Like 2-PBFRTC, N-PBFRTC uses a heuristic function to achieve quick path establishment. Unlike 2-PBFRTC, N-PBFRTC is fully scalable, in the sense that it is capable of employing any number of processors to compute the closure.
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