Using ACTs in Disjunctive Deductive Databases
نویسندگان
چکیده
This paper describes research eeorts to develop eecient implementation techniques for disjunctive deductive databases. The aim is to build a database engine that produces perfect model semantics as introduced by Przymusinski. When used with positive dis-junctive databases the results would be equivalent to that of minimal model semantics. Our strategy is to build Access Clause Trees (ACTs) based on the new data structure-Clause Trees, introduced by Horton and Spencer, to facilitate in building a two stage query processing engine. This engine builds the ACTs bottom up using the intensional database and then uses set-at-a-time evaluation to run the newly developed trees against the extensional database.
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