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FirstOrder Query Rewriting for Inconsistent Databases
, 2007
"... We consider the problem of retrieving consistent answers over databases that might be inconsistent with respect to a set of integrity constraints. In particular, we concentrate on sets of constraints that consist of key dependencies, and we give an algorithm that computes the consistent answers fo ..."
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Cited by 75 (2 self)
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for a large and practical class of conjunctive queries. Given a query q, the algorithm returns a firstorder query Q (called a query rewriting) such that for every (potentially inconsistent) database I, the consistent answers for q can be obtained by evaluating Q directly on I.
FirstOrder Queries over One Unary Function
"... This paper investigates the complexity of query problem for firstorder formulas on quasiunary signatures, that is, on vocabularies made of a single unary function and any number of monadic predicates. We first prove a form of quantifier elimination result: any query defined by a quasiunary first ..."
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Cited by 3 (2 self)
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This paper investigates the complexity of query problem for firstorder formulas on quasiunary signatures, that is, on vocabularies made of a single unary function and any number of monadic predicates. We first prove a form of quantifier elimination result: any query defined by a quasiunary firstorder
FirstOrder Queries over One Unary Function
"... Abstract. This paper investigates the complexity of query problem for firstorder formulas on quasiunary signatures, that is, on vocabularies made of a single unary function and any number of monadic predicates. We first prove a form of quantifier elimination result: any query defined by a quasiun ..."
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Cited by 1 (1 self)
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Abstract. This paper investigates the complexity of query problem for firstorder formulas on quasiunary signatures, that is, on vocabularies made of a single unary function and any number of monadic predicates. We first prove a form of quantifier elimination result: any query defined by a quasi
COMPUTING THE JTH SOLUTION OF A FIRSTORDER QUERY
 THEORETICAL INFORMATICS AND APPLICATIONS INFORMATIQUE
, 1999
"... We design algorithms of ”optimal” data complexity for several natural problems about firstorder queries on structures of bounded degree. For that purpose, we first introduce a framework to deal with logical or combinatorial problems R ⊂ I × O whose instances x ∈ I may admit of several solutions R(x ..."
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Cited by 3 (0 self)
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We design algorithms of ”optimal” data complexity for several natural problems about firstorder queries on structures of bounded degree. For that purpose, we first introduce a framework to deal with logical or combinatorial problems R ⊂ I × O whose instances x ∈ I may admit of several solutions R
Processing FirstOrder Queries under Limited Access Patterns
 IN PODS
, 2004
"... We study the problem of answering queries over sources with limited access patterns. Given a firstorder query Q, the problem is to decide whether there is an equivalent query which can be executed observing the access patterns restrictions. If so, we say that Q is feasible. We define feasible for f ..."
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Cited by 19 (2 self)
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We study the problem of answering queries over sources with limited access patterns. Given a firstorder query Q, the problem is to decide whether there is an equivalent query which can be executed observing the access patterns restrictions. If so, we say that Q is feasible. We define feasible
Firstorder queries on finite structures over the reals
"... We investigate properties of finite relational structures over the reals expressed by firstorder sentences whose predicates are the relations of the structure plus arbitrary polynomial inequalities, and whose quantifiers can range over the whole set of reals. In constraint programming terminology, ..."
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Cited by 33 (2 self)
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, this corresponds to Boolean real polynomial constraint queries on finite structures. The fact that quantifiers range over all reals seems crucial � however, we observe that each sentence in the firstorder theory of the reals can be evaluated by letting each quantifier range over only a finite set of real numbers
FirstOrder Queries on Databases Embedded in an Infinite Structure
 INF. PROC. LETT
, 1995
"... We consider "generic" (isomorphisminvariant) queries on relational databases embedded in an infinite background structure. Assume a generic query is expressible by a firstorder formula over the embedded domain that may involve both the relations of the database and the relations and func ..."
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Cited by 2 (1 self)
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We consider "generic" (isomorphisminvariant) queries on relational databases embedded in an infinite background structure. Assume a generic query is expressible by a firstorder formula over the embedded domain that may involve both the relations of the database and the relations
FIRSTORDER QUERY EVALUATION ON STRUCTURES OF Bounded Degree
 VOL. 7 (2:20) 2011, PP. 1–8
, 2011
"... ..."
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