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The Semantics Of Constraint Logic Programs
 JOURNAL OF LOGIC PROGRAMMING
, 1996
"... This paper presents for the first time the semantic foundations of CLP in a selfcontained and complete package. The main contributions are threefold. First, we extend the original conference paper by presenting definitions and basic semantic constructs from first principles, giving new and comp ..."
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Cited by 872 (14 self)
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This paper presents for the first time the semantic foundations of CLP in a selfcontained and complete package. The main contributions are threefold. First, we extend the original conference paper by presenting definitions and basic semantic constructs from first principles, giving new and complete proofs for the main lemmas. Importantly, we clarify which theorems depend on conditions such as solution compactness, satisfaction completeness and independence of constraints. Second, we generalize the original results to allow for incompleteness of the constraint solver. This is important since almost all CLP systems use an incomplete solver. Third, we give conditions on the (possibly incomplete) solver which ensure that the operational semantics is confluent, that is, has independence of literal scheduling.
Constraint Logic Programming: A Survey
"... Constraint Logic Programming (CLP) is a merger of two declarative paradigms: constraint solving and logic programming. Although a relatively new field, CLP has progressed in several quite different directions. In particular, the early fundamental concepts have been adapted to better serve in differe ..."
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Cited by 869 (25 self)
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Constraint Logic Programming (CLP) is a merger of two declarative paradigms: constraint solving and logic programming. Although a relatively new field, CLP has progressed in several quite different directions. In particular, the early fundamental concepts have been adapted to better serve in different areas of applications. In this survey of CLP, a primary goal is to give a systematic description of the major trends in terms of common fundamental concepts. The three main parts cover the theory, implementation issues, and programming for applications.
Efficient Maintenance of Materialized Mediated Views
 In SIGMOD
, 1995
"... Integrating data and knowledge from multiple heterogeneous sources  like databases, knowledge bases or specific software packages  is often required for answering certain queries. Recently, a powerful framework for defining mediated views spanning multiple knowledge bases by a set of constr ..."
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Cited by 55 (8 self)
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Integrating data and knowledge from multiple heterogeneous sources  like databases, knowledge bases or specific software packages  is often required for answering certain queries. Recently, a powerful framework for defining mediated views spanning multiple knowledge bases by a set of constrained rules (cf. work of Kanellakis et. al. [27]) was proposed [39, 5, 26]. Within this paper, we investigate the materialization of these views by unfolding the view definition and the efficient maintenance of the resulting materialized mediated view in case of updates. Thereby, we consider two kinds of updates: updates to the view and updates to the underlying sources. For each of these two cases several efficient algorithms maintaining materialized mediated views are given. We improve on previous algorithms like the DRed algorithm [22] and introduce a new fixpoint operator WP which  opposed to the standard fixpoint operator TP [19]  allows us to correctly capture the update'...
A Logic Programming View of CLP
 International Conference on Logic Programming
, 1993
"... We address the problem of lifting definitions, results, and even proofs for the theory of logic programming, so that they apply to constraint logic programming (CLP). We attempt to systematize this lifting, where it is possible, and delineate where it is not possible. We show that the Independence o ..."
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Cited by 48 (10 self)
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We address the problem of lifting definitions, results, and even proofs for the theory of logic programming, so that they apply to constraint logic programming (CLP). We attempt to systematize this lifting, where it is possible, and delineate where it is not possible. We show that the Independence of Negated Constraints property of constraint domains is fundamental to several different aspects of constraint logic programming. This is a principal cause for the inability to lift some traditional logic programming results to constraint logic programming. 1 Introduction We address the problem of lifting definitions, results, and even proofs for the theory of logic programming, so that they apply to constraint logic programming (CLP). (In viewing the theory of constraint logic programming as lifted from the theory of logic programming, we are taking a logic programming view of CLP.) Several papers have dealt with this problem for specific results, mostly inspired by the CLP Scheme [10, 11...
Constrained Dependencies
 Theoretical Computer Science
, 1995
"... We extend the notions of functional and finiteness dependencies to apply to subsets of a relation that are specified by constraints. These dependencies have many applications. We are able to characterize those constraint domains which admit a polynomial time solution of the implication problem (assu ..."
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Cited by 22 (0 self)
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We extend the notions of functional and finiteness dependencies to apply to subsets of a relation that are specified by constraints. These dependencies have many applications. We are able to characterize those constraint domains which admit a polynomial time solution of the implication problem (assuming P/=NP) and give an efficient algorithm for these cases, modulo the cost of constraint manipulation. For other cases we offer approximate algorithms. Finally, we outline some applications of these dependencies to the analysis and optimization of CLP programs and database queries.
Computing Nonground Representations of Stable Models
 Proceedings of the 4th International Conference on Logic Programming and Nonmonotonic Reasoning (LPNMR97), number 1265 in Lecture Notes in Computer Science
, 1997
"... Turi [20] introduced the important notion of a constrained atom: an atom with associated equality and disequality constraints on its arguments. A set of constrained atoms is a constrained interpretation. ..."
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Cited by 9 (0 self)
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Turi [20] introduced the important notion of a constrained atom: an atom with associated equality and disequality constraints on its arguments. A set of constrained atoms is a constrained interpretation.
A General Framework For Distributed Reason Maintenance
"... In this paper we will present an efficient logical and computational framework for distributed reason maintenance systems (DRMS), part of our implementation of a CKBSshell based upon results from distributed and deductive databases. We define a logic programming based foundation onto which paraco ..."
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In this paper we will present an efficient logical and computational framework for distributed reason maintenance systems (DRMS), part of our implementation of a CKBSshell based upon results from distributed and deductive databases. We define a logic programming based foundation onto which paraconsistent, uncertain, temporal and all kinds of distributed reason maintenance capabilities coping with uncertain and temporal informations as well can be added modularly. Compared to previous approaches, we remove limitations on the number of components and the need to define schemespecific semantics and resolution procedures. Our theoretical issues in this paper are backed by an ongoing implementation exploiting results from distributed databases. 1 INTRODUCTION With the transition from isolated to cooperating knowledge bases, there is an urgent need for sound computational reasoning with a variety of circumstancial information. Tracking of sources and circumstances as well as revis...