Dr. Theodoros Chondrogiannis

Post-doctoral Researcher

Theodoros studied computer science in his home country of Greece. He obtained his 4-year BSc degree in Computer Science and Technology with a focus on Software Systems from the Department of Computer Science and Technology of the University of Peloponnese in 2009, and his MSc degree in Advanced Information Systems from Department of Informatics and Telecommunications of the National Kapodistrian University of Athens in 2013. 

In 2013, Theodoros was awarded a PhD fellowship from the Free University of Bozen-Bolzano and he started his PhD at the  Faculty of Computer Science. In 2017, he completed successfully his PhD studies and received a doctorate for his thesis entitled Efficient Algorithms for Route Planning Problems on Road Networks. After his doctorate, he continued working as a postdoctolar researcher at the Faculty of Computer Science until December 2017, when he joined the University of Konstanz.  

Theodoros joined the Database and Information Systems group of the University of Konstanz on December 2017.

Areas of Interest

  • Route Planning
  • Path Query Processing
  • Graph Query Optimization
  • Multi-modal Transportation Network Analysis
  • Trajectory Data management and Analysis

Selected Publications

  1. Mehmet Aytimur, Silvan Reiner, Leonard Wörteler, Theodoros Chondrogiannis, Michael Grossniklaus. LPLM: A neural language model for cardinality estimation of like-queries. Proc. of the ACM on Management of Data 2024 paper.
  2. Theodoros Chondrogiannis, Michael Grossniklaus. Highway systems: How good are they, really? SSTD 2023 (best paper award) paper
  3. Leonard Wörteler, Moritz Renftle, Theodoros Chondrogiannis, Michael Grossniklaus. Cardinality Estimation using Label Probability Propagation for Subgraph Matching in Property Graph Databases. EDBT 2022 paper.
  4. Christian Häcker, Panagiotis Bouros, Theodoros Chondrogiannis, Ernst Althaus. Most Diverse Near-Shortest Paths. ACM SIGSPATIAL GIS 2021 paper
  5. Manuel Hotz, Theodoros Chondrogiannis, Leonard Wörteler, Michael Grossniklaus. Online Landmark-Based Batch Processing of Shortest Path Queries. SSDBM 2021 paper
  6. Theodoros Chondrogiannis, Panagiotis Bouros, Johann Gamper, Ulf Leser, David B. Blumenthal, Finding k-shortest paths with limited overlap, The VLDB Journal 2020 paper source
  7. Camila F. Costa, Theodoros Chondrogiannis, Mario A. Nascimento, Panagiotis Bouros: RRAMEN: An Interactive Tool for Evaluating Choices and Changes in Transportation Networks. EDBT  2020: 599-602 paper video source
  8. Dimitris Sacharidis, Panagiotis Bouros, Theodoros Chondrogiannis. Finding the most preferred path. ACM SIGSPATIAL GIS 2017. paper
  9. Ttheodoros Chondrogiannis, Johann Gamper. Pardisp: A partition-based framework for distance and shortest path queries on road networks. In IEEE Int. Conf. on Mobile Data Management, IEEE MDM 2016. paper source



  • Publicity chair of the 18th International Symposium on Spatial and Temporal Databases (SSTD'23), 2023 
  • Co-chair of the 5th ACM SIGSPATIAL Student Research Competition, 2020 
  • Co-chair of the 4th ACM SIGSPATIAL Student Research Competition, 2019 
  • Web-chair of the 16th International Symposium on Spatial and Temporal Databases (SSTD'19), 2019 
  • Web-chair of the 30th International Conference on Scientific and Statistical Database Management (SSDBM'18), 2018 

Programme Committees

  • 31st ACM International Conference on Information and Knowledge Management (CIKM'22), 2022
  • 23rd International Conference on Web Information Systems Engineering (WISE'22), 2022
  • 27th International Conference on Database Systems for Advanced Applications (DASFAA'22), 2022
  • 22nd International Conference on Web Information Systems Engineering (WISE'21), 2021
  • 26th International Conference on Database Systems for Advanced Applications (DASFAA'21), 2021
  • 21st IEEE International Conference on Mobile Data Management - Demo Track (MDM'20), 2020
  • 25th International Conference on Database Systems for Advanced Applications (DASFAA'20), 2020
  • 21st International Conference on Web Information Systems Engineering (WISE'20), 2020