Database Systems

Welcome to the web presence of the Database Research Group at University of Tübingen.

Our group pursues a variety of “all-time classic” database research questions—prime examples include query language design, translation, and optimization—but with a few twists:

We are particularly interested in the design, compilation, and optimization of expressive database languages that support rich data models and embed seamlessly into host programming languages. This regularly leads us to explore the intersection of database and programming language technology.
Whenever insightful and promising, we apply techniques that have their roots in the programming languages community to the database research domain. This paves the way for expressive and elegant language-integrated queries, new query compilation techniques, and novel query optimization strategies.

We love to teach the basics as well as the intricacies of database systems. Courses on query and programming language technology are found in our repertoire as well.

News

Denis Hirn

Feb 26 2025

The DuckDB Explain Visualizer is now available!

We are happy to announce the release of the DuckDB Explain Visualizer! It is a web-based tool that allows you to visualize the query plans of DuckDB. The DuckDB Explain Visualizer is available here: https://db.cs.uni-tuebingen.de/explain.

What is the DuckDB Explain Visualizer?

If you spend any significant amount of time looking at DuckDB query plans, sooner or later you will realize that the textual representation of the query plan has its limitations. It can be hard to read and understand, especially for complex plans. And worse, if the plan is too large, it can be cut off, making it impossible to understand the full plan. Also, there are no visual cues to help you understand the plan, find bottlenecks, or identify optimization opportunities.

Trampoline-Style Queries for SQL will be at CIDR 2025

We love the single-track system-focused CIDR series of conferences and we are happy to be able join the community again for CIDR 2025, once more located in Amsterdam (NL), January 19-22, 2025. Together with our colleagues Thomas Neumann and Altan Birler of TU Munich, we discuss a new foundation for iterative queries: we step away from fixpoints and instead bank on Trampoline-Style queries for SQL, a concept inspired by the programming languages and compilers domain. WITH TRAMPOLINE has already been prototypically implemented in Thomas’ Umbra RDBMS. Trampolines are versatile—they also serve as the backbone for our work in the compilation of imperative-style programs to SQL.

A Fix for the Fixation on Fixpoints accepted at CIDR 2023

Tübingen returns to CIDR, this time for the 2023 edition to be held in Amsterdam (NL), January 8–11, 2023. We will report on our recent explorations into alternative forms of iteration in SQL—generalizing recursive common table expressions—that are easier to write and read as well as more efficient to evaluate than WITH RECURSIVE (which has been established more than 20 years ago but since then has been largely left untouched).