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27
The logic of constraint satisfaction
, 1992
"... The constraint satisfaction problem (CSP) formalization has been a productive tool within Artificial Intelligence and related areas. The finite CSP (FCSP) framework is presented here as a restricted logical calculus within a space of logical representation and reasoning systems. FCSP is formulated i ..."
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Cited by 265 (5 self)
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in a variety of logical settings: theorem proving in first order predicate calculus, propositional theorem proving (and hence SAT), the Prolog and Datalog approaches, constraint network algorithms, a logical interpreter for networks of constraints, the constraint logic programming (CLP) paradigm
Answering Recursive Queries Using Views
 In PODS
, 1997
"... 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. Previous work on answering queries using views restricted queries to being conjunctive. We extend this work to general recurs ..."
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Cited by 205 (9 self)
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recursive queries: Given a datalog program P and a set of views, is it possible to find a datalog program that is equivalent to P and only uses views as EDB predicates? In this paper, we show that the problem of whether a datalog program can be rewritten into an equivalent program that only uses views
Magicsets Transformation in Nonrecursive Systems
 In Proceedings of the Eleventh Symposium on Principles of Database Systems (PODS
, 1992
"... this paper we will write database queries in datalog [Ull89]. Datalog is the language of horn clause logic rules, written as "ifthen" rules. A datalog rule is required to be rangerestricted: it must define a finite relation for the predicate in the head of the rule. In this paper we will ..."
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Cited by 8 (2 self)
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this paper we will write database queries in datalog [Ull89]. Datalog is the language of horn clause logic rules, written as "ifthen" rules. A datalog rule is required to be rangerestricted: it must define a finite relation for the predicate in the head of the rule. In this paper we
Implementing Dataflow Optimizations for Pegasus in Datalog
"... Recent work by Lam et al. [1, 2, 3] has investigated the use of the logicprogramming language Datalog to code program analyses, exploiting a fast implementation of Datalog using binary decision diagrams. Analyses written in Datalog are more compact and easier to reason about than handcoded version ..."
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and transformations on them, in Datalog. We therefore propose to connect Whaley and Lamâ€™s bddbddb implementation of Datalog to the CASH compiler, and use it to implement some dataflow analyses. In Datalog, programs are specified as sets of inference rules defining predicates, as in Prolog. Prolog interprets inference
Preservation of Integrity Constraints in Definite Datalog Programs
"... Given a program P and two sets IC and IC 0 of integrity constraints, IC uniformly implies IC 0 in P if whenever an (input) database I defined on predicates of P satisfies IC then the (output) database computed by P from I satisfies IC 0 . P preserves IC if IC uniformly implies IC in P . We co ..."
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consider only definite DATALOG programs. We show that testing preservation of downwardclosed integrity constraints can be simplified to the case of singlerule programs that are computed in a "nonrecursive manner". Specially, we present an efficient test algorithm when constraints are equality
The Expressive Power of SPARQL
"... Abstract. This paper studies the expressive power of SPARQL. The main result is that SPARQL and nonrecursive safe Datalog with negation have equivalent expressive power, and hence, by classical results, SPARQL is equivalent from an expressive point of view to Relational Algebra. We present explicit ..."
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Cited by 76 (3 self)
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Abstract. This paper studies the expressive power of SPARQL. The main result is that SPARQL and nonrecursive safe Datalog with negation have equivalent expressive power, and hence, by classical results, SPARQL is equivalent from an expressive point of view to Relational Algebra. We present
Answering queries using views over description logics knowledge bases
 IN: PROC. OF THE 17TH NAT. CONF. ON ARTIFICIAL INTELLIGENCE (AAAI 2000
, 2000
"... Answering queries using views amounts to computing the answer to a query having information only on the extension of a set of precomputed queries (views). This problem is relevant in several fields, such as information integration, query optimization, and data warehousing, and has been studied recen ..."
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Cited by 60 (27 self)
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recently in different settings. In this paper we address answering queries using views in a setting where intensional knowledge about the domain is represented using a very expressive Description Logic equipped with nary relations, and queries are nonrecursive datalog queries whose predicates
Query Containment for Data Integration Systems
"... The problem of query containment is fundamental to many aspects of database systems, including query optimization, determining independence of queries from updates, and rewriting queries using views. In the data integration framework, however, the standard notion of query containment does not suffic ..."
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Cited by 57 (1 self)
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a recursive datalog program over the sources. Finally, we provide tight bounds for variants of relative containment when the queries and source descriptions may contain comparison predicates.
The Complexity Of Querying Indefinite Information: Defined Relations, Recursion And Linear Order
, 1992
"... This dissertation studies the computational complexity of answering queries in logical databases containing indefinite information arising from two sources: facts stated in terms of defined relations, and incomplete information about linearly ordered domains. First, we consider databases consisting ..."
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Cited by 8 (0 self)
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of (1) a DATALOG program and (2) a description of the world in terms of the predicates defined by the program as well as the basic predicates. The query processing problem in such databases is related to issues in database theory, including view updates and DATALOG optimization, and also
Magic Conditions
, 1990
"... Much recent work has focussed on the bottomup evaluation of Datalog programs. One approach, called magicsets, is based on rewriting a logic program so that bottomup fixpoint evaluation of the program avoids generation of irrelevant facts ([BMSU86, BR87, Ram88]). It is widely believed that the prin ..."
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Cited by 29 (5 self)
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Much recent work has focussed on the bottomup evaluation of Datalog programs. One approach, called magicsets, is based on rewriting a logic program so that bottomup fixpoint evaluation of the program avoids generation of irrelevant facts ([BMSU86, BR87, Ram88]). It is widely believed
Results 1  10
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27