Research

Research Topics

• Evolution in Data Engineering Processes
• Self-adapting Data Engineering Methods and Processes
• Evolution of NoSQL Databases
• Abstractions over Data
• Profiling in Non-Relational Databases
• Methods for Automatic Data Curation

Projects

• NoSQL Schema Evolution and Big Data Migration at Scale II (DFG, 2022-24) 
• NoSQL Schema Evolution and Big Data Migration at Scale (DFG, 2018-21)

Project Meeting: 14.-17. October 2024

To intensify our cooperation with the University of Hagen, we were invited to Hagen. There we discussed about linking our research topics with a focus on schema evolution, meta-model integration and data engineering pipelines.

MODELS 2024

We attended the 27th International Conference on Model Driven Engineering Languages and Systems (MODELS) in Linz, Austria were we enjoyed inspiring talks and discussions about modeling approaches.

• Dominique Hausler, Meike Klettke: Nautilus: Implementation of an Evolution Approach for Graph Databases. MoDELS (Companion) 2024
• Dominique Hausler: Estimation, Impact and Visualization of Schema Evolution in Graph Databases. MoDELS (Companion) 2024

Project Meeting: 18.-20. June 2024

During our project meeting in Regensburg we had inspiring discussions about schema evolution and data preprocessing topics as well as eventful days with our colleagues from the University of Hagen and the University of Passau.

SIGMOD 2024

Sebastian Strasser presented his work on the importance of transparency in the context of data preprocessing and its impact on machine learning approaches, at the HILDA Workshop co-located with SIGMOD International Conference on Management of Data in Santiago de Chile.

Sebastian Strasser, Meike Klettke: Transparent Data Preprocessing for Machine Learning, HILDA@SIGMOD 2024

ER 2023

Together with our project partners from the University of Hagen we attended the 42nd International Conference on Conceptual Modeling in Lisbon, Portugal from Nov 6, 2023 - Nov 9, 2023 and presented our ongoing work and first results on an evolution language for graph databases.

Dominique Hausler, Meike Klettke, Uta Störl: A Language for Graph Database Evolution and its Implementation in Neo4j. ER (Companion), 2023

LWDA 2023

At this year's LWDA (Oct 9, 2023 - Oct 11, 2023, Marburg, Germany) we presented the first paper, all of our chair members contributed to. Topic wise the article illustrates the challenges facing, when working with NoSQL databases, in contrast to relational databases.

Mark Lukas Möller, Dominique Hausler, Sebastian Strasser, Tanja Auge, Meike Klettke: Heterogeneity in NoSQL Databases - Challenges of Handling schema-less Data. LWDA 2023

3. DFG-Projekttreffen: 4.-6. Oktober 2023

Vom 4.-6. Oktober 2023 haben wir mit den Projekt-Kolleg:innen aus Hagen und Passau das Projekttreffen des DFG-Projektes "NoSQL Schema Evolution and Big Data Migration at Scale" durchgeführt. Bei dem dreitägigen Treffen standen intensive Diskussionen über die Arbeiten im DFG-Projekt, die Themen Multi-model Databases und Data Engineering Pipelines sowie die Zusammenarbeit in diesem Themenfeldern im Mittelpunkt.

ProvenanceWeek 2023

We presented two papers at this year's ProvenanceWeek (April 30-May 1, Austin, TX, USA): 

• Provenance for Lattice QCD workflows by Tanja Auge, Gunnar Bali, Meike Klettke, Bertram Ludäscher, Wolfgang Söldner, Simon Weishäupl, Tilo Wettig (pdf). 
• ProSA: A provenance system for reproducing query results by Tanja Auge (pdf).

A short report about further highlights of the workshop can be found here.

2. DFG-Projekttreffen: NoSQL Schema Evolution and Big Data Migration at Scale II

Vom 17.-19. April fand in Nürnberg das Projekttreffen statt, diesmal in einer etwas größeren Runde. Die Gruppen von Prof. Störl (FernUniversität in Hagen), Prof. Scherzinger (Universität Passau) und wir trafen uns im dortigen Schulungszentrum der FernUniversität Hagen. 

Beeindruckend war die Themenbreite: vom Vergleich von verschiedenen Data Engineering Pipeline Tools, dem Einsatz von Quantencomputern für verschiedene Datenbank-Optimierungsaufgaben, der Ableitung von Schema-Versionen aus heterogenen Daten, von Metamodellen für Polystores und optimierter Datenspeicherung in diesen bis hin zur Ableitung von conditional functional dependencies. Es ist zunehmend interessant, die Synergie-Effekte der langjährigen Zusammenarbeit zu sehen. 

EDBT 2023

28th March - 31st March 2023: Together with Stefan Klessinger and Stefanie Scherzinger at the EDBT 2023 in Ioannina, Greece. We organise the 3. CoMoNoS workshop there and Stefan presented this demo.

Stefan Klessinger, Michael Fruth, Valentin Gittinger, Meike Klettke, Uta Störl, Stefanie Scherzinger: Tagger: A Tool for the Discovery of Tagged Unions in JSON Schema Extraction, Demo-Track, EDBT 2023

1. DFG-Projekttreffen: NoSQL Schema Evolution and Big Data Migration at Scale II

Am 21./22.09.2022 fand das Projekttreffen des DFG-Projektes statt. Die Gruppen von Prof. Störl (FernUniversität in Hagen) und Prof. Scherzinger (Universität Passau) waren zu Gast am Lehrstuhl für Data Engineering.

Im Mittelpunkt des Projekttreffens standen die Themen: Realisierung von Schema-Evolution in Polystores, Metamodelle für Polystores sowie Ableitung von conditional functional dependencies und inclusion dependencies aus heterogenen Daten.