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Data Exchange: Semantics and Query Answering
TLDR
We give an algebraic specification that selects, among all solutions to the data exchange problem, a special class of solutions that we call universal. Expand
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Data exchange: semantics and query answering
TLDR
We give an algebraic specification that selects, among all solutions to the data exchange problem, a special class of solutions that we call universal. Expand
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Composing Schema Mappings: Second-Order Dependencies to the Rescue
TLDR
We give a rigorous semantics to the composition of schema mappings in which the specification is given by a finite set of source-to-target tuple-generating dependencies and investigate the definability and computational complexity of the composition. Expand
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Data exchange: getting to the core
TLDR
Data exchange is the problem of taking data structured under a source schema and creating an instance of a target schema that reflects the source data as accurately as possible. Expand
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On the decision problem for two-variable first-order logic
TLDR
We improve Mortimer's bound by one exponential and show that every satisfiable FO2-sentence has a model whose size is at most exponential in the size of the sentence. Expand
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Repair checking in inconsistent databases: algorithms and complexity
TLDR
In this paper, we give a polynomial-time algorithm for subset-repair checking under integrity constraints that are the union of a weakly acyclic set of local-as-view (LAV) tuple-generating dependencies and a set of equality-generative dependencies. Expand
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Conjunctive-query containment and constraint satisfaction
TLDR
We show that several cases of tractable nonuniform constraint-satisfaction problems do indeed uniformize and give rise to polynomial-time solvable cases of constraint satisfaction and conjunctive-query containment. Expand
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Schema mappings, data exchange, and metadata management
TLDR
We present an overview of recent advances in data exchange and metadata management, where the schema mappings are between relational schemas. Expand
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Finite Model Theory and Its Applications
TLDR
Unifying Themes in Finite Model Theory.- On the Expressive Power of Logics on Finite Models. Expand
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Conjunctive-Query Containment and Constraint Satisfaction
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