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@inproceedings{DBLP:conf/pods/MumickFPR90,
author = {Inderpal Singh Mumick and
Sheldon J. Finkelstein and
Hamid Pirahesh and
Raghu Ramakrishnan},
title = {Magic Conditions},
booktitle = {Proceedings of the Ninth ACM SIGACT-SIGMOD-SIGART Symposium on
Principles of Database Systems, April 2-4, 1990, Nashville, Tennessee},
publisher = {ACM Press},
year = {1990},
isbn = {0-89791-352-3},
pages = {314-330},
ee = {http://doi.acm.org/10.1145/298514.298584, db/conf/pods/MumickFPR90.html},
crossref = {DBLP:conf/pods/90},
bibsource = {DBLP, http://dblp.uni-trier.de}
}
Much recent work has focussed on the bottom-up evaluation of Datalog programs. One approach, called Magic-Sets, is based on rewriting a logic program so that bottom-up fixpoint evaluation of the program avoids generation of irrelevant facts ([BMSU86, BR87, Ram88]). It is widely believed that the principal application of the Magic-Sets technique is to restrict computation in recursive queries using equijoin predicates. We extend the Magic-Set transformation to use predicates other than equality (X > 10, for example). This Extended Magic-Set technique has practical utility in "real" relational databases, not only for recursive queries, but for non-recursive queries as well; in ([MFPR9O]) we use the results in this paper and those in [MPR89] to define a magic-set transformation for relational databases supporting SQL and its extensions, going on to describe an implementation of magic in Starburst ([HFLP89]). We also give preliminary performance measurements.
In extending Magic-Sets, we describe a natural generalization of the common class of bound (b) and free (f) adornments. We also present, a formalism to compare adornment classes.
Copyright © 1990 by the ACM, Inc., used by permission. Permission to make digital or hard copies is granted provided that copies are not made or distributed for profit or direct commercial advantage, and that copies show this notice on the first page or initial screen of a display along with the full citation.
