Compiling Separable Recursions

Report ID: TR-140-88
Author: Naughton, Jeffrey F.
Date: 1988-03-00
Pages: 28
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Abstract:

In this paper we consider evaluating queries on relations defined by a combination of recursive rules. We first define separable recursions. We then give a specialized algorithm for evaluating selections on separable recursions. Like the Magic Sets and Counting algorithms, this algorithm uses selection constants to avoid examining irrelevant portions of the database; however, on some simple recursions this algorithm is O(n), whereas the Magic Sets algorithm is omega(n2) and the Generalized Counting Method is omega(2n).