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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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Cited by 23 (3 self)
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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...
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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Cited by 20 (1 self)
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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...
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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Cited by 20 (3 self)
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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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Cited by 9 (0 self)
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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 ..."
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Cited by 7 (2 self)
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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. 1 Introduction Constraint databases is an active area of current research. In particular, linear constraint databases have been used for modeling geometric data and in other applications [3, 14, 15, 22, 23]. There are several proposals to define query languages for linear constraint databases. Most query language proposals are based on firstorder logic. However, it has been found that firstorder languages even with real polynomial constraint databases are ...
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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Cited by 5 (1 self)
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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
"... ..."
Finitely Representable Nested Relations
"... this paper is the definition of a model and a query language for finitely representable nested relations, overcoming some limitations of the previous proposals. Our language is obtained by extending ..."
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Cited by 1 (1 self)
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this paper is the definition of a model and a query language for finitely representable nested relations, overcoming some limitations of the previous proposals. Our language is obtained by extending
Problem Solving in the DISCO Constraint Database System
 In Proc. Constraint Databases and Applications
, 1997
"... . This paper describes general approaches to solving two classes of problems using the DISCO constraint database system. The first class of problems occurs when distinct values from a subset of the integers must be assigned to the variables of a constraint satisfaction problem. The second occurs whe ..."
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. This paper describes general approaches to solving two classes of problems using the DISCO constraint database system. The first class of problems occurs when distinct values from a subset of the integers must be assigned to the variables of a constraint satisfaction problem. The second occurs when a group of items must be selected from a subset of the integers such that each of a set of constraints holds. 1 Introduction DISCO [1] is a constraint database system with a unique combination of two features: (1) it can accept (integer and set) constraint databases as inputs and (2) it can find a (constraint) database representation of the whole fixpoint model of each program on any given input database. No other system can do both. Constraint logic programming systems with sets like CLPS [7], Conjuncto [4], ECLIPSE [3], and flogg [2] can do (1) but cannot do (2). Database systems like CORAL [9] and LDL [15] can do (2) but cannot do (1). The unique combination of achieving both (1) and (...