(MSc Research Project / MSc Thesis) Character maps in database systems are specialized data structures optimized for efficient string handling. Similar to Bloom filters, they allow quick checks for the presence of characters or substrings without full string comparisons. This makes them useful for accelerating string-related queries and improving overall search performance in databases. The goal …
Supervisors: Martin Hentschel
Semester: Fall 2025
Tags: query optimizer

(MSc Research Project / MSc Thesis) DuckDB stores data in a database file. The database file is split into partitions, and for each partition, DuckDB keeps statistics in the form of min-max summaries. Similar min-max summaries exist in Parquet files and many other database systems, such as Snowflake. Check out Lecture 8 of last semester’s Introduction to Database Systems course for a summary …
Supervisors: Martin Hentschel
Semester: Fall 2025
Tags: query optimizer

Query optimization is crucial for any data management system to achieve good performance. Recent advancements in AI have led academia and industry to investigate learning-based techniques in query optimization. In particular, many works propose replacing the cost model used during plan enumeration with a machine learning model that estimates the runtime of a plan. However, to build such a model …
Supervisors: Zoi Kaoudi
Semester: Fall 2025
Tags: machine learning, training data, query optimizer