• Corpus ID: 4992977

Loop Restricted Existential Rules and First-order Rewritability for Query Answering

  title={Loop Restricted Existential Rules and First-order Rewritability for Query Answering},
  author={Vernon Asuncion and Yan Zhang and Heng Zhang},
  booktitle={International Conference on Principles of Knowledge Representation and Reasoning},
In ontology-based data access (OBDA), the classical database is enhanced with an ontology in the form of logical assertions generating new intensional knowledge. A powerful form of such logical assertions is the tuple-generating dependencies (TGDs), also called existential rules, where Horn rules are extended by allowing existential quantifiers to appear in the rule heads. In this paper we introduce a new language called loop restricted (LR) TGDs (existential rules), which are TGDs with certain… 



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