KR2023Proceedings of the 20th International Conference on Principles of Knowledge Representation and ReasoningProceedings of the 20th International Conference on Principles of Knowledge Representation and Reasoning

Rhodes, Greece. September 2-8, 2023.

Edited by

ISSN: 2334-1033
ISBN: 978-1-956792-02-7

Sponsored by
Published by

Copyright © 2023 International Joint Conferences on Artificial Intelligence Organization

A Framework for Combining Entity Resolution and Query Answering in Knowledge Bases

  1. Ronald Fagin(IBM Almaden Research Center)
  2. Phokion G. Kolaitis(University of California Santa Cruz, IBM Research)
  3. Domenico Lembo(Sapienza University of Rome)
  4. Lucian Popa(IBM Almaden Research Center)
  5. Federico Scafoglieri(Sapienza University of Rome)


  1. Ontology-based data access, integration, and exchange
  2. Applications of KR in databases
  3. Description logics
  4. Dealing with uncertain, incomplete or contradictory information


We propose a new framework for combining entity resolution and query answering in knowledge bases (KBs) with tuple-generating dependencies (tgds) and equality-generating dependencies (egds) as rules. We define the semantics of the KB in terms of special instances that involve equivalence classes of entities and sets of values. Intuitively, the former collect all entities denoting the same real-world object, while the latter collect all alternative values for an attribute. This approach allows us to both resolve entities and bypass possible inconsistencies in the data. We then design a chase procedure that is tailored to this new framework and has the feature that it never fails; moreover, when the chase procedure terminates, it produces a universal solution, which in turn can be used to obtain the certain answers to conjunctive queries. We finally discuss challenges arising when the chase does not terminate.