Welcome to the Database Research Group

The Database Research Group is part of the Department of Computer Science at the University of Salzburg, Austria. Our research interests include data-centric applications in database and information systems with a particular focus on similarity search queries over large data collections, for example, approximate matching of strings and trees, efficient indexes for distance computations, and top-k queries. Other fields of research include load balancing algorithms for distributed frameworks like MapReduce and queries in geographic information systems. The research results are new algorithms with performance guarantees, which are implemented and evaluated on the motivating application.

Nikolaus Augsten
Head of the Database Research Group
Martin Schäler
Deputy Head of the Database Research Group


Paper at SIGMOD 2023
Our paper "FINEX: A Fast Index for Exact & Flexible Density-Based Clustering" has been accepted at the ACM International Conference on Management of Data (SIGMOD) 2023.
Paper at ICDE 2023
Our paper "MetricJoin: Leveraging Metric Properties for Robust Exact Set Similarity Joins" has been accepted at the IEEE International Conference on Data Engineering (ICDE) 2023.
Three Open Topic Professorships at University of Salzburg
Three open topic professorships are to be filled within the framework of the "Excellence in Digital Sciences and Interdisciplinary Technologies" Initiative (EXDIGIT) at the University of Salzburg. Deadline: Oct 24, 2022. Official job post: §-99-1-EXDIGIT-englisch-1.pdf
Disseminate Podcast
Thomas Hütter talks about our JSON Edit Distance (JEDI) on Jack Waudby's Disseminate Podcast.
Presentation at ACSD 2022
Thomas Hütter presents his work on JSON similarity queries at the Austrian Computer Science Day (ACSD) 2022.
Presentation at SIGMOD 2022
A pre-recorded video of the presentation of our SIGMOD paper "JEDI: These aren't the JSON documents you're looking for..." can be found [HERE].
Paper at Information Systems Journal
Our paper on ensuring differential privacy on streams title "Swellfish privacy: Supporting time-dependent relevance for continuous differential privacy" has been accepted for Information Systems Journal.
Nikolaus Augsten on sabbatical leave until September 2022
Nikolaus Augsten is on sabbatical leave until September 2022. During this time, Martin Schäler leads the Database Group including all associated facilities.
Paper at SIGMOD 2022
Our paper on similarity queries for JSON documents with the title "JEDI: These aren't the JSON documents you're looking for..." has been accepted at the ACM International Conference on Management of Data (SIGMOD) 2022.
New Digital Humanities Project on Biblical Online Synopsis
Our research project "BOSS 1.0: Biblical Online Synopsis Salzburg 1.0" has been funded by Federal State of Salzburg.
New FWF Project on Similarity Queries
Our research project "DESQ - Declarative and Efficient Similarity Queries" has been funded by Austrian Science Fund (FWF). Find more details [HERE].
Paper at HardBD (ICDE Workshop) and DASFAA
Our co-authored paper "An Investigation of Atomic Synchronization for Sort-Based Group-By Aggregation on GPUs" got accepted at the Joint International Workshop on Big Data Management on Emerging Hardware and Data Management on Virtualized Active Systems (HardBD@ICDE2021). The paper investigates how to minimize the synchronization overhead for efficient sort-based group-by-aggregate computations on GPUs. Our co-authored paper "Accurate Cardinality Estimation of Co-occurring Words Using Suffix Trees" got accepted at the International Conference on Database Systems for Advanced Applications (DASFAA) 2021. The paper allows accurate and fast estimation the expected frequencies of arbitrary word groups using suffix trees relevant e.g., for sophisticated physical relational operator selection.
An article in Süddeutsche Zeitung refers to the work of one of our group members
The research of our colleague Martin Schäler in the ESQUIRE project on privacy-preserving data analysis was mentioned in news paper article in Süddeutsche Zeitung. The work was done when he was still at the Karlsruhe Institute of Technology (Karlsruhe, Germany) shortly before joining the Database Group in Salzburg.
Best Paper Invitation – ADBIS 2020
Our paper An Efficient Index for Reachability Queries in Public Transport Networks was invited as one of the best papers of ADBIS 2020 to a special issue of Information Systems Frontiers (Springer). Congratulations to Bezaye and Mateusz, and thanks to our co-authors C.S. Jensen, Aalborg University, and M. Böhlen, University of Zurich.
ERC Starting Grant at Our Department
Congratulations to Sebastian Forster (Efficient Algorithms Group) for being awarded the prestigious ERC Starting Grant for his project "Dynamic Algorithms Against Strong Adversaries" (DynASoAr). What a great success!
Paper at CIKM 2020
Our paper "Minimal Edit-Based Diffs for Large Trees" has been accepted at the ACM International Conference on Information and Knowledge Management (CIKM) 2020. The source code, data, and experiments are available on the Tree Edit Distance website.
Paper at ADBIS 2020
Our paper "An Efficient Index for Reachability Queries in Public Transport Networks" got accepted at the European Conference on Advances in Databases and Information Systems (ADBIS) 2020.
Publication of the Month May
Our paper "DeSignate: detecting signature characters in gene sequence alignments for taxon diagnoses" (BMC Bioinformatics 2020) has been awarded as Publication of the Month May by the Department of Biosciences, University of Salzburg. [Read more]
ACM SIGMOD Reproducibility Badge
Our paper "A Scalable Index for Top-k Subtree Similarity Queries" (SIGMOD 2019) has been awarded the ACM Results Replicated label, which indicates that "the experimental results of the paper were replicated by the committee and were found to support the central results reported in the paper". All relevant source code and data will soon be available from ACM DL.
Paper at BMC Bioinformatics
In an interdisciplinary project with the Department of Biosciences we have developed DeSignate, a tool for the identification of molecular characters for taxon diagnoses. DeSignate is freely available as a web application and open source. The resulting paper was recently published in the BMC Bioinformatics Journal.
Data Science for Databases: Paper at SIGMOD 2020
April 15, 2020
Our paper A Relational Matrix Algebra and its Implementation in a Column Store (joint work with researchers from the University of Zurich) was accepted for publication at SIGMOD 2020. The paper proposes an extension of SQL for linear algebra operations. The extension was implemented (github project) in the main memory database MonetDB and was shown to outperform solutions based on R and Python/NumPy.
"Salzburger Nachrichten" reports about our research success
Salzburger Nachrichten published an article on our recent results on tree similarity queries. The work discussed in this article was presented at ICDE 2020 and SIGMOD 2020. Congratulations to Thomas Hütter, Daniel Kocher, and Mateusz Pawlik, the main contributors to this work.
Leibniz Prize 2020 for Database Systems research
Thomas Neumann, professor in database systems at TU Munich, receives the Gottfried Wilhelm Leibniz Prize 2020 for his outstanding and influential work on main memory database systems. The Leibniz Prize is among the most prestigious and highest endowed research prizes in Germany. This is a great success and honors for the field of database systems. Congratulations, Thomas!
Top research rating for our Computer Science Department, Salzburg
In the newest U-Multirank our department has been ranked highest in research among all participating universities. In German-speaking countries, we're leading in top cited publications and interdisciplinary publications, and our citation rate is ranked third. A press release can be found on our university's website.
Thomas Hütter wins Young Investigators Award
Our two PhD students, Thomas Hütter and Daniel Kocher, were finalists for the Young Investigators Award 2019 at the University of Salzburg. Thomas won the 1st price for his work "Effective Filters and Linear Time Verification for Tree Similarity Joins".
Paper at SIGMOD 2019
Our paper "A Scalable Index for Top-k Subtree Similarity Queries" got accepted at the ACM Special Interest Group on Management of Data (SIGMOD) 2019.
Paper at ICDE 2019
Our paper "Effective Filters and Linear Time Verification for Tree Similarity Joins" got accepted at the IEEE International Conference on Data Engineering (ICDE) 2019.
Paper at VLDB 2018
Our paper Set Similarity Joins on MapReduce: An Experimental Survey (joint work with researchers from Berlin and Mainz) got accepted at the Very Large Data Bases Conference (VLDB) 2018.
Paper at SISAP 2017
Our paper "A New Perspective on the Tree Edit Distance" by Stefan Schwarz, Mateusz Pawlik, and Nikolaus Augsten has been published and presented in Munich at SISAP 2017 conference. You can read it [HERE].
Invited Talk - Austrian Computer Science Day
Nikolaus Augsten presented an invited talk "Effiziente Techniken für Ähnlichkeitsabfragen in hierarchischen Daten" at ACSD 2017 / IMAGINE 2017 in Vienna. The slides are available for download.
Informatiker der Woche
Nikolaus Augsten interviewed as "Informatiker der Woche" (computer scientist of the week). Find the full interview [HERE].
Kurt-Zopf Award for Best Paper
Our TODS paper on the efficient computation of the tree edit distance received the Kurt-Zopf-Förderpreis awarded by University of Salzburg to the best journal paper 2015.
New project funded
Our research project "FFTED - Fast and Flexible Tree Edit Distance" has been funded by Austrian Science Fund (FWF). Find more details [HERE].