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

  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},
  pages={701 - 718}
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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