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DLOG
2011
12 years 7 months ago
Goal-oriented Query Rewriting for OWL 2 QL
We present an optimized query rewriting algorithm for OWL 2 QL that computes the rewriting set of a user query by avoiding unnecessary inferences and extended clause subsumption ch...
Alexandros Chortaras, Despoina Trivela, Giorgos B....
VLDB
1987
ACM
100views Database» more  VLDB 1987»
13 years 7 months ago
Optimization of Systems of Algebraic Equations for Evaluating Datalog Queries
A Datalog program can be translated into a system of fixpoint equations of relational algebra; this paper studies how such a system can be solved and optimized for a particular qu...
Stefano Ceri, Letizia Tanca
PODS
1992
ACM
100views Database» more  PODS 1992»
13 years 7 months ago
On the Equivalence of Recursive and Nonrecursive Datalog Programs
: We study the problem of determining whether a given recursive Datalog program is equivalent to a given nonrecursive Datalog program. Since nonrecursive Datalog programs are equiv...
Surajit Chaudhuri, Moshe Y. Vardi
PODS
1997
ACM
149views Database» more  PODS 1997»
13 years 7 months ago
Answering Recursive Queries Using Views
We consider the problem of answering datalog queries using materialized views. The ability to answer queries using views is crucial in the context of information integration. Prev...
Oliver M. Duschka, Michael R. Genesereth