David Justen

TU Berlin, BIFOLD
Big Data Engineering Group (DAMS Lab)
Faculty IV - Electrical Engineering and Computer Science

Room B-113, Hardenbergstraße 40A, 10623 Berlin
david.justen@tu-berlin.de

I am PhD student at Technische Universität Berlin, supervised by Prof. Matthias Boehm and member of the BIFOLD Graduate School. Prior to this, I was a researcher at Prof. Hasso Plattner’s Enterprise Platform and Integration Concepts (EPIC) chair at the Hasso Plattner Institute in Potsdam. My research focusses on query optimization for analytical database systems and cloud-based data processing. Specifically, I am looking into adaptive query processing and robust plan generation to reduce the effects of erroneous cardinality estimates.

Publications

  • Thomas Bodner, Theo Radig, David Justen, Daniel Ritter, Tilmann Rabl:
    An Empirical Evaluation of Serverless Cloud Infrastructure for Large-Scale Data Processing
    EDBT 2025 [pre-print, paper, code] 👑 best paper

  • David Justen, Daniel Ritter, Campbell Fraser, Andrew Lamb, Nga Tran, Allison Lee, Thomas Bodner, Mhd Yamen Haddad, Steffen Zeuch, Volker Markl, Matthias Boehm:
    POLAR: Adaptive and Non-invasive Join Order Selection via Plans of Least Resistance PVLDB 2024 [paper, slides, poster, repro]

  • David Justen:
    Cost-efficiency and Performance Robustness in Serverless Data Exchange
    SRC@SIGMOD 2022 [paper]

Teaching

  • Information Systems and Data Analytics [SS25]
  • Programming Practical: Data Systems [WS23, SS24]
  • Research and Implementation of Database Concepts (HPI) [WS22]
  • Develop Your Own Database (HPI) [SS22]
  • Trends and Concepts of Business Application Architecture (HPI) [SS22]

Thesis Supervision

  • Marcel Scholand: Skewed Data Generation for Realistic Data Warehouse Workloads. 2024
  • Paul Pohlitz: Adaptive Join Processing as a DuckDB Extension. 2024

Work Experience

  • October ‘23 - present
    Doctoral Researcher @ Technische Universität, Berlin, DE
  • March ‘22 - September ‘23
    Doctoral Reseracher @ Hasso Plattner Institute, Potsdam, DE
  • October ‘19 - March ‘20
    Software Development Intern @ SAP, New York, US
  • March ‘18 - June ‘18
    Software Development Intern @ Native Instruments, Berlin, DE

Education

  • 2018 - 2022
    IT-Systems Engineering (M.Sc.), Hasso Plattner Institute (University of Potsdam)
    Thesis: Cost-efficiency and Performance Robustness in Serverless Join Processing
  • 2015 - 2018
    Media Computer Science (B.Sc.), Berlin University of Applied Sciences and Technology
    Thesis: Evolving Neural Networks to Steer Autonomous Agents in a Labyrinth

Unrelated Interests

Besides my work as a researcher I am an active member of TAMLI, a charitable organization that supervises young adults and delegates them to a voluntary service in a home for people with special needs in Israel. I am also a part-time DJ - so hit me up if you happen to know how to get a booking for Andy Pavlo’s database courses.