A Fast Algorithm for Query Optimization in Universal Relation Databases
نویسندگان
چکیده
The method of the canonical connection introduced by Maier and Ullman provides an optimal procedure for query processing in universal-relation databases. We present an algorithm for computing canonical connections in a database scheme which is more efficient than the classical algorithm based on tableau reduction. Moreover, with a slight modification of the algorithm we obtain a join plan which succeeds in controlling the nonmonotonicity of cyclic canonical connections. ] 1998 Academic Press
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تاریخ انتشار 1995