An O(N2) equivalence algorithm for fan-out free queries
An equivalence algorithm for fan-out free queries, which form an untyped subclass of conjunctive queries, based on an extension of the implication graph technique is presented. This algorithm runs in O(n2) time where n is the size of the queries involved. This algorithm subsumes all known equivalence testing algorithms for various subclasses of fan-out free queries.
KeywordsSymbol Mapping Horn Clause Graph Isomorphism Conjunctive Query Pruning Process
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