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Partition Constraints for Conjunctive Queries: Bounds and Worst-Case Optimal Joins

Authors Kyle Deeds , Timo Camillo Merkl

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  • Theory of computation → Database theory
Keywords
  • Worst-Case Optimal Joins
  • Cardinality Bounds
  • Degeneracy
  • Degree Constraints
  • Partition Constraints

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Abstract

In the last decade, various works have used statistics on relations to improve both the theory and practice of conjunctive query execution. Starting with the AGM bound which took advantage of relation sizes, later works incorporated statistics like functional dependencies and degree constraints. Each new statistic prompted work along two lines; bounding the size of conjunctive query outputs and worst-case optimal join algorithms. In this work, we continue in this vein by introducing a new statistic called a partition constraint. This statistic captures latent structure within relations by partitioning them into sub-relations which each have much tighter degree constraints. We show that this approach can both refine existing cardinality bounds and improve existing worst-case optimal join algorithms.

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Kyle Deeds and Timo Camillo Merkl. Partition Constraints for Conjunctive Queries: Bounds and Worst-Case Optimal Joins. In 28th International Conference on Database Theory (ICDT 2025). Leibniz International Proceedings in Informatics (LIPIcs), Volume 328, pp. 17:1-17:18, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2025) https://doi.org/10.4230/LIPIcs.ICDT.2025.17

Author Details

Kyle Deeds
  • University of Washington, Seattle, WA, USA
Timo Camillo Merkl
  • TU Wien, Austria

Funding

  • Deeds, Kyle: Was supported by the NSF SHF 2312195 and NSF IIS 2314527 grants.
  • Merkl, Timo Camillo: Was supported by the Vienna Science and Technology Fund (WWTF) [10.47379/ICT2201, 10.47379/VRG18013].

Acknowledgements

Part of this work was done when the authors were visiting the Simons Institute for the Theory of Computing.

References

  1. Christopher R. Aberger, Andrew Lamb, Susan Tu, Andres Nötzli, Kunle Olukotun, and Christopher Ré. Emptyheaded: A relational engine for graph processing. ACM Trans. Database Syst., 42(4):20:1-20:44, 2017. URL: https://doi.org/10.1145/3129246.
  2. Albert Atserias, Martin Grohe, and Dániel Marx. Size bounds and query plans for relational joins. SIAM Journal on Computing, 42(4):1737-1767, 2013. URL: https://doi.org/10.1137/110859440.
  3. Suman K. Bera, Lior Gishboliner, Yevgeny Levanzov, C. Seshadhri, and Asaf Shapira. Counting subgraphs in degenerate graphs. J. ACM, 69(3):23:1-23:21, 2022. URL: https://doi.org/10.1145/3520240.
  4. Suman K. Bera, Noujan Pashanasangi, and C. Seshadhri. Linear time subgraph counting, graph degeneracy, and the chasm at size six. In Thomas Vidick, editor, 11th Innovations in Theoretical Computer Science Conference, ITCS 2020, January 12-14, 2020, Seattle, Washington, USA, volume 151 of LIPIcs, pages 38:1-38:20. Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2020. URL: https://doi.org/10.4230/LIPICS.ITCS.2020.38.
  5. Suman K. Bera, Noujan Pashanasangi, and C. Seshadhri. Near-linear time homomorphism counting in bounded degeneracy graphs: The barrier of long induced cycles. In Dániel Marx, editor, Proceedings of the 2021 ACM-SIAM Symposium on Discrete Algorithms, SODA 2021, Virtual Conference, January 10 - 13, 2021, pages 2315-2332. SIAM, 2021. URL: https://doi.org/10.1137/1.9781611976465.138.
  6. Suman K. Bera and C. Seshadhri. How the degeneracy helps for triangle counting in graph streams. In Dan Suciu, Yufei Tao, and Zhewei Wei, editors, Proceedings of the 39th ACM SIGMOD-SIGACT-SIGAI Symposium on Principles of Database Systems, PODS 2020, Portland, OR, USA, June 14-19, 2020, pages 457-467. ACM, 2020. URL: https://doi.org/10.1145/3375395.3387665.
  7. Marco Bressan and Marc Roth. Exact and approximate pattern counting in degenerate graphs: New algorithms, hardness results, and complexity dichotomies. In 62nd IEEE Annual Symposium on Foundations of Computer Science, FOCS 2021, Denver, CO, USA, February 7-10, 2022, pages 276-285. IEEE, 2021. URL: https://doi.org/10.1109/FOCS52979.2021.00036.
  8. Kyle Deeds and Timo Camillo Merkl. Partition constraints for conjunctive queries: Bounds and worst-case optimal joins [technical report], 2025. URL: https://arxiv.org/abs/2501.04190.
  9. Kyle Deeds, Dan Suciu, Magda Balazinska, and Walter Cai. Degree sequence bound for join cardinality estimation. In Floris Geerts and Brecht Vandevoort, editors, 26th International Conference on Database Theory, ICDT 2023, March 28-31, 2023, Ioannina, Greece, volume 255 of LIPIcs, pages 8:1-8:18. Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2023. URL: https://doi.org/10.4230/LIPICS.ICDT.2023.8.
  10. Kyle B. Deeds, Dan Suciu, and Magdalena Balazinska. Safebound: A practical system for generating cardinality bounds. Proc. ACM Manag. Data, 1(1):53:1-53:26, 2023. URL: https://doi.org/10.1145/3588907.
  11. Jack Edmonds. Minimum partition of a matroid into independent subsets. J. Res. Nat. Bur. Standards Sect. B, 69:67-72, 1965. Google Scholar
  12. Michael J. Freitag, Maximilian Bandle, Tobias Schmidt, Alfons Kemper, and Thomas Neumann. Adopting worst-case optimal joins in relational database systems. Proc. VLDB Endow., 13(11):1891-1904, 2020. URL: http://www.vldb.org/pvldb/vol13/p1891-freitag.pdf.
  13. Lior Gishboliner, Yevgeny Levanzov, Asaf Shapira, and Raphael Yuster. Counting homomorphic cycles in degenerate graphs. ACM Trans. Algorithms, 19(1):2:1-2:22, 2023. URL: https://doi.org/10.1145/3560820.
  14. Georg Gottlob, Stephanie Tien Lee, Gregory Valiant, and Paul Valiant. Size and treewidth bounds for conjunctive queries. J. ACM, 59(3):16:1-16:35, 2012. URL: https://doi.org/10.1145/2220357.2220363.
  15. Martin Grohe and Dániel Marx. Constraint solving via fractional edge covers. In Proceedings of the Seventeenth Annual ACM-SIAM Symposium on Discrete Algorithms, SODA 2006, Miami, Florida, USA, January 22-26, 2006, pages 289-298. ACM Press, 2006. URL: http://dl.acm.org/citation.cfm?id=1109557.1109590.
  16. Yuxing Han, Ziniu Wu, Peizhi Wu, Rong Zhu, Jingyi Yang, Liang Wei Tan, Kai Zeng, Gao Cong, Yanzhao Qin, Andreas Pfadler, Zhengping Qian, Jingren Zhou, Jiangneng Li, and Bin Cui. Cardinality estimation in DBMS: A comprehensive benchmark evaluation. Proc. VLDB Endow., 15(4):752-765, 2021. URL: https://doi.org/10.14778/3503585.3503586.
  17. Mahmoud Abo Khamis, Vasileios Nakos, Dan Olteanu, and Dan Suciu. Join size bounds using l_p-norms on degree sequences. Proc. ACM Manag. Data, 2(2):96, 2024. URL: https://doi.org/10.1145/3651597.
  18. Mahmoud Abo Khamis, Hung Q. Ngo, and Dan Suciu. Computing join queries with functional dependencies. In Tova Milo and Wang-Chiew Tan, editors, Proceedings of the 35th ACM SIGMOD-SIGACT-SIGAI Symposium on Principles of Database Systems, PODS 2016, San Francisco, CA, USA, June 26 - July 01, 2016, pages 327-342. ACM, 2016. URL: https://doi.org/10.1145/2902251.2902289.
  19. Mahmoud Abo Khamis, Hung Q. Ngo, and Dan Suciu. What do shannon-type inequalities, submodular width, and disjunctive datalog have to do with one another? In Emanuel Sallinger, Jan Van den Bussche, and Floris Geerts, editors, Proceedings of the 36th ACM SIGMOD-SIGACT-SIGAI Symposium on Principles of Database Systems, PODS 2017, Chicago, IL, USA, May 14-19, 2017, pages 429-444. ACM, 2017. URL: https://doi.org/10.1145/3034786.3056105.
  20. Viktor Leis, Andrey Gubichev, Atanas Mirchev, Peter A. Boncz, Alfons Kemper, and Thomas Neumann. How good are query optimizers, really? Proc. VLDB Endow., 9(3):204-215, 2015. URL: https://doi.org/10.14778/2850583.2850594.
  21. Hung Q. Ngo, Ely Porat, Christopher Ré, and Atri Rudra. Worst-case optimal join algorithms: [extended abstract]. In Michael Benedikt, Markus Krötzsch, and Maurizio Lenzerini, editors, Proceedings of the 31st ACM SIGMOD-SIGACT-SIGART Symposium on Principles of Database Systems, PODS 2012, Scottsdale, AZ, USA, May 20-24, 2012, pages 37-48. ACM, 2012. URL: https://doi.org/10.1145/2213556.2213565.
  22. Hung Q. Ngo, Christopher Ré, and Atri Rudra. Skew strikes back: new developments in the theory of join algorithms. SIGMOD Rec., 42(4):5-16, 2013. URL: https://doi.org/10.1145/2590989.2590991.
  23. Shixuan Sun and Qiong Luo. In-memory subgraph matching: An in-depth study. In David Maier, Rachel Pottinger, AnHai Doan, Wang-Chiew Tan, Abdussalam Alawini, and Hung Q. Ngo, editors, Proceedings of the 2020 International Conference on Management of Data, SIGMOD Conference 2020, online conference [Portland, OR, USA], June 14-19, 2020, pages 1083-1098. ACM, 2020. URL: https://doi.org/10.1145/3318464.3380581.
  24. Todd L. Veldhuizen. Triejoin: A simple, worst-case optimal join algorithm. In Nicole Schweikardt, Vassilis Christophides, and Vincent Leroy, editors, Proc. 17th International Conference on Database Theory (ICDT), Athens, Greece, March 24-28, 2014, pages 96-106. OpenProceedings.org, 2014. URL: https://doi.org/10.5441/002/ICDT.2014.13.
  25. Yisu Remy Wang, Max Willsey, and Dan Suciu. Free join: Unifying worst-case optimal and traditional joins. Proc. ACM Manag. Data, 1(2):150:1-150:23, 2023. URL: https://doi.org/10.1145/3589295.
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