Efficient Evaluation of Visual Queries Using Deductive Databases
نویسندگان
چکیده
We report on the eeciency of queries formulated with the Hy + /GraphLog data vi-sualization system, a substantial application which utilizes the CORAL deductive database system. Hy + itself has been used in a number of application areas, including software engineering, network management, and the debugging of distributed programs. We focus on the translation of GraphLog queries to CORAL programs as well as the performance of the resultant programs on large data sets. One source of ineeciency in programs involving recursion and query constants is that CORAL is not able to detect that the programs are factorable. We provide an alternative translation which always propagates constants to base relations, with a consequent improvement in performance.
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