Short Bio

I am an associate professor in computer science at the Vrije Universiteit Brussel (VUB) where I lead a database research subgroup within SOFT. Our research lies on the intersection of data management systems and theoretical computer sciences with current focus on formal foundations of scalable data management technologies. This includes (distributed) query processing with formal optimality guarantees, concurrency theory for high-available transaction processing systems, and optimizations for querying data in complex heterogeneous systems like the web.

I obtained a Ph.D. from Hasselt University in 2017 under the advice of Frank Neven and was a postdoctoral researcher at the Swiss Federal Institute of Technology in Lausanne (EPFL) where I worked with Christoph Koch. As a Ph.D. student, I did internships at the University of Washington in Seattle, the University of Wisconsin in Madison, and the technical University of Dortmund.

More: Institutional Page · LinkedIn · X · ResearchGate · ORCID · Math Genealogy

News

  • Two new researchers joined our team. Welcome Avi and Sampriti!
  • Tim Baccaert recently got the chance to visit the university of California - Berkeley for several months, to work with prof. Hellerstein. He also obtained an FWO travelgrant for this research stay.
  • Dr. Heba Mohamed obtained a prestigious FWO postdoctoral fellowship.

Awards and Prizes

Team

  • Dr. Heba (Aamer) Mohamed (FWO fellow)
  • Dr. Sampriti Roy
  • Tim Baccaert
  • Fernando Hechavarría Fajardo
  • Avi Tomar

If you are interested in collaborating with us (internship or other type of research collaboration), don't hesitate to reach out. We welcome visitors.

Recent Publications (full list)

Author order depends on the collaboration; often alphabetical, or semi-alphabetical (with junior researcher(s) first)

  • (upcoming)
    Tim Baccaert, Bas Ketsman. A Generalized CALM Theorem for Non-Deterministic Computation in Asynchronous Distributed Systems. In: Information Systems. 2025. Volume - No -.
  • PVLDB 2025
    Brecht Vandevoort, Alan D. Fekete, Bas Ketsman, Frank Neven, Stijn Vansummeren. Using Read Promotion and Mixed Isolation Levels for Performant Yet Serializable Execution of Transaction Programs. In: Proceedings of the VLDB Endownment. 2025. Volume 18 No 9.
  • TOCL 2025
    Bas Ketsman, Frank Neven, Brecht Vandevoort. Parallel-Correctness and Transferability for Conjunctive Queries under Bag Semantics. In: ACM Transactions on Computational Logic. 2025. Volume 26 No 2. DOI:10.1145/3712291.
  • TODS 2025
    Brecht Vandevoort, Bas Ketsman, Frank Neven. Allocating Isolation Levels to Transactions in a Multiversion Setting. In: ACM Transactions on Database Systems. 2025. Volume 50 No 2. DOI:10.1145/3716374.
  • ICDT 2025
    Heba Aamer, Bas Ketsman. PAC:Computing Join Queries with Semi-Covers. In: International Conference on Data Engineering (PhD symposium). 2025. DOI:10.4230/LIPIcs.ICDT.2025.6.
  • ICDE 2024
    Tim Baccaert, Bas Ketsman. Cascade: Optimal Transaction Scheduling for High-Contention Workloads. In: International Conference on Data Engineering (PhD symposium). 2024. DOI:10.1109/ICDE60146.2024.00452.
  • PACMOD 2024
    Brecht Vandevoort, Bas Ketsman, Frank Neven. When View- and Conflict-Robustness Coincide for Multiversion Concurrency Control. In: Proceedings of the ACM on Management of Data. 2024. Volume 2 No 2. DOI:10.1145/3651592.
  • SIGMOD Record 2024
    Brecht Vandevoort, Bas Ketsman, Frank Neven. Allocating Isolation Levels to Transactions in a Multiversion Setting. In: SIGMOD Record 2024. 2024. Volume 53 No 1. DOI:10.1145/3716374.
  • TPLP 2024
    Bart Bogaerts, Bas Ketsman, Younes Zeboudj, Heba Aamer, Ruben Taelman, Ruben Verborgh. Distributed Subweb Specifications for Traversing the Web. In: Theory and Practice of Logic Programming. 2024. Volume 24 No 2. DOI:10.1017/S1471068423000054.
See also: DBLP · Google Scholar

Teaching & Services

Teaching at VUB

  • Databases - Master (spring 2020 - now)
  • Databanken - Bachelor (spring 2020 - now)
  • Scalable Data Management Systems - Master (spring 2020, autumn 2020 - now)
  • Open Information Systems - Master (autumn 2020 with Bart Bogaerts, autumn 2021)
  • Data and Information Management - Master (autumn 2022)
  • Advanced Topics in Big Data - Master (spring 2022 with Beat Signer)

Conference and Workshop Organization

International Services

  • PC membership
    PODS (2020,2023,2025), ICDT (2020,2023,2026), Doctoral Consortium @ RuleML+RR (2024)
  • Other reviewing
    PODS (2017,2018), VLDBJ (2018), TOCS (2018), ACM TODS (2015, 2016, 2021), Elsevier IS (2015)

Talks

  • UC Berkeley, 2023
    Negation, Coordination and Monotonicity. Sky Computing. Berkeley, CA, USA [online talk]. 12 April 2023.
  • EDBT, 2023
    Detecting Robustness against MVRC for Transaction Programs with Predicate Reads. International Conference on Extending Database Technology. Ioannina, Greece [online talk]. 31 March 2023.
  • Northeastern University, 2022
    Datalog with Negation and Monotonicity. DATA Lab @ Northeastern. online. 28 July 2022.
  • ICDT, 2020
    Datalog with Negation and Monotonicity. International Conference on Database Theory. Copenhagen, Denmark [online talk due to the COVID-19 pandemy]. 30 March 2020.
  • UC San Diego, 2018
    Datalog, Coordination and Monotonicity. University of California. San Diego, CA, USA. 4 October 2018.
  • ICDT, 2018
    Distribution Policies for Datalog. International Conference on Database Theory. Vienna, Austria. 26 March 2018.
  • Stanford University, 2017
    Coordination-free query evaluation and multi-query optimization in parallel and distributed systems. Stanford University. Stanford, CA, USA. 18 October 2017.
  • UC Berkeley, 2017
    Coordination-free query evaluation and multi-query optimization in parallel and distributed systems. University of California. Berkeley, CA, USA. 14 August 2017.
  • PODS, 2017
    A Worst-Case Optimal Multi-Round Algorithm for Parallel Computation of Conjunctive Queries. Principles of Database Systems Conference. Chicago, IL, USA. 17 May 2017.
  • UW Madison, 2017
    A Worst-Case Optimal Multi-Round Algorithm for Parallel Computation of Conjunctive Queries. University of Wisconsin. Madison, WI, USA. 10 April 2017.
  • DBDBD, 2016
    A Worst-Case Optimal Multi-Round Algorithm for Parallel Computation of Conjunctive Queries on Graphs. Dutch Belgian Database Day. Mons, Belgium. 28 October 2016.
  • UW Seattle, 2016
    Single-Round Multi-Join Evaluation. University of Washington. Seattle, WA, USA. 8 April 2016.
  • PODS, 2015
    Parallel-Correctness and Transferability for Conjunctive Queries. Principles of Database Systems Conference. Melbourne, VIC, Australia. 1 June 2015.
  • ICDT, 2015
    Optimal Broadcasting Strategies for Conjunctive Queries over Distributed Data. International Conference on Database Theory. Brussels, Belgium. 25 March 2015.
  • PODS, 2014
    Weaker Forms of Monotonicity for Declarative Networking: a more fine-grained answer to the CALM-conjecture. Principles of Database Systems Conference. Snowbird, Utah, USA. 22 June 2014.
  • DBDBD, 2014
    How to Stay CALM While Seeing What is not There?. Dutch Belgian Database Day. Antwerp, Belgium. 17 October 2014.