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Minimization of Tree Pattern Queries

Published: 15 June 2016 Publication History

Abstract

We investigate minimization of tree pattern queries that use the child relation, descendant relation, node labels, and wildcards. We prove that minimization for such tree patterns is Sigma2P-complete and thus solve a problem first attacked by Flesca, Furfaro, and Masciari in 2003. We first provide an example that shows that tree patterns cannot be minimized by deleting nodes. This example shows that the M-NR conjecture, which states that minimality of tree patterns is equivalent to their nonredundancy, is false. We then show how the example can be turned into a gadget that allows us to prove Sigma2P-completeness.

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Cited By

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  • (2022)Answering Queries Using Views, Second EditionundefinedOnline publication date: 26-Feb-2022
  • (2021)Inferring Deterministic Regular Expression with Unorder and CountingDatabase Systems for Advanced Applications10.1007/978-3-030-73197-7_15(235-252)Online publication date: 11-Apr-2021
  • (2018)Minimization of Tree PatternsJournal of the ACM10.1145/318028165:4(1-46)Online publication date: 25-Jul-2018
  • Show More Cited By

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Published In

cover image ACM Conferences
PODS '16: Proceedings of the 35th ACM SIGMOD-SIGACT-SIGAI Symposium on Principles of Database Systems
June 2016
504 pages
ISBN:9781450341912
DOI:10.1145/2902251
  • General Chair:
  • Tova Milo,
  • Program Chair:
  • Wang-Chiew Tan
Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than the author(s) must be honored. Abstracting with credit is permitted. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from [email protected].

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Publication History

Published: 15 June 2016

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Author Tags

  1. XML
  2. XPath
  3. complexity
  4. graph databases
  5. optimization
  6. tree patterns
  7. trees

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  • Research-article

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SIGMOD/PODS'16
Sponsor:
SIGMOD/PODS'16: International Conference on Management of Data
June 26 - July 1, 2016
California, San Francisco, USA

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PODS '16 Paper Acceptance Rate 31 of 94 submissions, 33%;
Overall Acceptance Rate 642 of 2,707 submissions, 24%

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Cited By

View all
  • (2022)Answering Queries Using Views, Second EditionundefinedOnline publication date: 26-Feb-2022
  • (2021)Inferring Deterministic Regular Expression with Unorder and CountingDatabase Systems for Advanced Applications10.1007/978-3-030-73197-7_15(235-252)Online publication date: 11-Apr-2021
  • (2018)Minimization of Tree PatternsJournal of the ACM10.1145/318028165:4(1-46)Online publication date: 25-Jul-2018
  • (2018)Conjunctive query containment over trees using schema informationActa Informatica10.1007/s00236-016-0282-155:1(17-56)Online publication date: 1-Feb-2018
  • (2017)Optimizing Tree Patterns for Querying Graph- and Tree-Structured DataACM SIGMOD Record10.1145/3093754.309375946:1(15-22)Online publication date: 12-May-2017
  • (2017)Technical PerspectiveACM SIGMOD Record10.1145/3093754.309375846:1(14-14)Online publication date: 12-May-2017
  • (2017)Optimizing tree pattern queries: why cutting is not enough (invited talk)Proceedings of the 49th Annual ACM SIGACT Symposium on Theory of Computing10.1145/3055399.3079076(3-3)Online publication date: 19-Jun-2017

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