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Strategic directions in constraint programming
 ACM Computing Surveys
, 1996
"... A constraint can be thought of intuitively as a restriction on a space of possibilities. Mathematical constraints are precisely specifiable relations ..."
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A constraint can be thought of intuitively as a restriction on a space of possibilities. Mathematical constraints are precisely specifiable relations
The C³ Constraint ObjectOriented Database System
, 1996
"... Constraints provide a flexible and uniform way to conceptually represent diverse data capturing spatiotemporal behavior, complex modeling requirements, partial and incomplete information etc, and have been used in a wide variety of application domains. Constraint databases have recently emerged to ..."
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Constraints provide a flexible and uniform way to conceptually represent diverse data capturing spatiotemporal behavior, complex modeling requirements, partial and incomplete information etc, and have been used in a wide variety of application domains. Constraint databases have recently emerged to deeply integrate data captured by constraints in databases. This paper reports on the development of the first constraint objectoriented database system, C³, and describes its specification, design and implementation. The C³ system is designed to be used for both implementation and optimization of highlevel constraint objectoriented query languages such as LyriC or constraint extensions of OQL, and for directly building software systems requiring extensible use of constraint database features. The C³ data manipulation language, Constraint Comprehension Calculus, is an integration constraint calculus for extensible constraint domains within monoid comprehensions, which s...
Constraint Databases: A Survey
 Semantics in Databases, number 1358 in LNCS
, 1998
"... . Constraint databases generalize relational databases by finitely representable infinite relations. This paper surveys the state of the art in constraint databases: known results, remaining open problems and current research directions. The paper also describes a new algebra for databases with inte ..."
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. Constraint databases generalize relational databases by finitely representable infinite relations. This paper surveys the state of the art in constraint databases: known results, remaining open problems and current research directions. The paper also describes a new algebra for databases with integer order constraints and a complexity analysis of evaluating queries in this algebra. In memory of Paris C. Kanellakis 1 Introduction There is a growing interest in recent years among database researchers in constraint databases, which are a generalization of relational databases by finitely representable infinite relations. Constraint databases are parametrized by the type of constraint domains and constraint used. The good news is that for many parameters constraint databases leave intact most of the fundamental assumptions of the relational database framework proposed by Codd. In particular, 1. Constraint databases can be queried by constraint query languages that (a) have a semantics ba...
An Extended Algebra for Constraint Databases
 IEEE Transactions on Knowledge and Data Engineering
, 1999
"... Constraint relational databases use constraints to both model and query data. A constraint relation contains a finite set of generalized tuples. Each generalized tuple is represented by a conjunction of constraints on a given logical theory and, depending on the logical theory and the specific conju ..."
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Constraint relational databases use constraints to both model and query data. A constraint relation contains a finite set of generalized tuples. Each generalized tuple is represented by a conjunction of constraints on a given logical theory and, depending on the logical theory and the specific conjunction of constraints, it may possibly represent an infinite set of relational tuples. For their characteristics, constraint databases are well suited to model multidimensional and structured data, like spatial and temporal data. The definition of an algebra for constraint relational databases is important in order to make constraint databases a practical technology. In this paper, we extend the previously defined constraint algebra (called generalized relational algebra). First, we show that the relational model is not the only possible semantic reference model for constraint relational databases and we show how constraint relations can be interpreted under the nested relational model. Then...
Quantifierelimination for the firstorder theory of boolean algebras with linear cardinality constraints
 In Proc. Advances in Databases and Information Systems (ADBIS’04), volume 3255 of LNCS
, 2004
"... Abstract. We present for the firstorder theory of atomic Boolean algebras of sets with linear cardinality constraints a quantifier elimination algorithm. In the case of atomic Boolean algebras of sets, this is a new generalization of Boole’s wellknown variable elimination method for conjunctions o ..."
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Abstract. We present for the firstorder theory of atomic Boolean algebras of sets with linear cardinality constraints a quantifier elimination algorithm. In the case of atomic Boolean algebras of sets, this is a new generalization of Boole’s wellknown variable elimination method for conjunctions of Boolean equality constraints. We also explain the connection of this new logical result with the evaluation of relational calculus queries on constraint databases that contain Boolean linear cardinality constraints. 1
Safe Datalog Queries with Linear Constraints
 IN PROCEEDINGS OF THE 4TH INTERNATIONAL CONFERENCE ON PRINCIPLES AND PRACTICE OF CONSTRAINT PROGRAMMING (CP98), NUMBER 1520 IN LNCS
, 1998
"... In this paper we consider Datalog queries with linear constraints. We identify several syntactical subcases of Datalog queries with linear constraints, called safe queries, and show that the least model of safe Datalog queries with linear constraints can be evaluated bottomup in closedform. These s ..."
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In this paper we consider Datalog queries with linear constraints. We identify several syntactical subcases of Datalog queries with linear constraints, called safe queries, and show that the least model of safe Datalog queries with linear constraints can be evaluated bottomup in closedform. These subcases include Datalog with only positive and upperbound or only negative and lower bound constraints or only halfaddition, upper and lower bound constraints. We also study other subcases where the recognition problem is decidable.
Refining Restriction Enzyme Genome Maps
 Constraints, V
, 1997
"... A genome map is an ordering of a set of clones according to their believed position on a DNA string. Simple heuristics for genome map assembly based on single restriction enzyme with complete digestion data can lead to inaccuracies and ambiguities. This paper presents a method that adds additional c ..."
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A genome map is an ordering of a set of clones according to their believed position on a DNA string. Simple heuristics for genome map assembly based on single restriction enzyme with complete digestion data can lead to inaccuracies and ambiguities. This paper presents a method that adds additional constraint checking to the assembly process. An automaton is presented that for any genome map produces a refined genome map where both the clones and the restriction fragments in each clone are ordered satisfying natural constraints called step constraints. Any genome map that cannot be refined is highly likely to be inaccurate and can be eliminated as a possibility. 1 Introduction Deoxyribonucleic acid or DNA, the genetic material that encodes the blueprint of any living organism, is composed of a string of nucleotides that are adenine (A), thymine (T), cytosine (C), and guanine (G). Clones are copies of random substrings of a given DNA string. Clones may overlap in a clone database. Restr...
Constraint Programming: Strategic Directions
 CONSTRAINTS: AN INTERNATIONAL JOURNAL
, 1997
"... ..."
Constraint Programming
, 1996
"... Machine, which has proven extremely successful in the context of logic programming. The WAM approach essentially provides a view of the compilation of these languages as a generalization of the standard techniques used in conventional languages, allowing most of the conventional optimizations. Glob ..."
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Machine, which has proven extremely successful in the context of logic programming. The WAM approach essentially provides a view of the compilation of these languages as a generalization of the standard techniques used in conventional languages, allowing most of the conventional optimizations. Global Analysis. As a result of the compilationbased approach the performance of current systems is quite acceptable when running code where generalpurpose constraint solving is performed. On the other hand, this approach alone cannot always provide performance in the control component that is competitive with other languages. In particular, their performance often does not reach that of traditional logic programming systems in symbolic applications and is generally far from that of traditional imperative programming languages in (non constraint related) numerical applications. The most generally accepted solution to this has been to develop advanced compilation technology capable of detecting ...