Estimating the Size of Generalized Transitive Closures
نویسندگان
چکیده
We present a framework for the estimation of the size of binary recursively defined relations. We show how the framework can be used to provide estimating algo rithms for the size of the transitive closure and generalizations of the transitive closure, and also show that for bounded degree relations, the algorithm runs in linear time. Such estimating algorithms are essential if database systems that support recursive relations or fixpoints are to be able to optimize queries and avoid infeasible computations.
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