Diversity of Answers to Conjunctive Queries

Authors Timo Camillo Merkl, Reinhard Pichler, Sebastian Skritek

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Timo Camillo Merkl
  • TU Wien, Austria
Reinhard Pichler
  • TU Wien, Austria
Sebastian Skritek
  • TU Wien, Austria

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Timo Camillo Merkl, Reinhard Pichler, and Sebastian Skritek. Diversity of Answers to Conjunctive Queries. In 26th International Conference on Database Theory (ICDT 2023). Leibniz International Proceedings in Informatics (LIPIcs), Volume 255, pp. 10:1-10:19, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2023)


Enumeration problems aim at outputting, without repetition, the set of solutions to a given problem instance. However, outputting the entire solution set may be prohibitively expensive if it is too big. In this case, outputting a small, sufficiently diverse subset of the solutions would be preferable. This leads to the Diverse-version of the original enumeration problem, where the goal is to achieve a certain level d of diversity by selecting k solutions. In this paper, we look at the Diverse-version of the query answering problem for Conjunctive Queries and extensions thereof. That is, we study the problem if it is possible to achieve a certain level d of diversity by selecting k answers to the given query and, in the positive case, to actually compute such k answers.

Subject Classification

ACM Subject Classification
  • Information systems → Data management systems
  • Query Answering
  • Diversity of Solutions
  • Complexity
  • Algorithms


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