Disjunctive datalog with existential quantifiers: Semantics, decidability, and complexity issues

@article{Alviano2012DisjunctiveDW,
title={Disjunctive datalog with existential quantifiers: Semantics, decidability, and complexity issues},
author={Mario Alviano and Wolfgang Faber and Nicola Leone and M. Manna},
journal={Theory and Practice of Logic Programming},
year={2012},
volume={12},
pages={701 - 718}
}
• Published 1 July 2012
• Computer Science
• Theory and Practice of Logic Programming
Abstract Datalog is one of the best-known rule-based languages, and extensions of it are used in a wide context of applications. An important Datalog extension is Disjunctive Datalog, which significantly increases the expressivity of the basic language. Disjunctive Datalog is useful in a wide range of applications, ranging from Databases (e.g., Data Integration) to Artificial Intelligence (e.g., diagnosis and planning under incomplete knowledge). However, in recent years an important…

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The precise objective of the doctoral thesis is to investigate the impact on the complexity of query answering, of adding disjunction to well-known decidable Datalog+/- fragments, namely guarded, sticky and weakly-acyclic Datalogy+/- theories.

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