Database Theory

From International Center for Computational Logic

Database Theory

Course with SWS 4/2/0 (lecture/exercise/practical) in SS 2020




  • 4/2/0


Examination method

  • Oral exam

Databases are a key technology in computer science that brings together fascinating theoretical topics and highly relevant practical applications. The goal of this lecture is to give an extended introduction to this interesting field, with a special focus on database query languages, their expressive power, and computational complexity. The lecture will introduce the relational data model, and then discuss theoretical and practical aspects of a variety of query languages:

  • first-order logic as a query language and the relational algebra
  • conjunctive queries and their unions
  • navigational queries: path queries
  • Datalog and its relatives
  • query answering under database dependencies

The lecture focuses on core principles that apply to many types of databases alike (relational, graph-based, semantic web). Some important query answering algorithms are presented, too, but otherwise, the details of database implementation and administration are not covered.


Undergraduate-level knowledge of predicate logic, regular languages, and algorithmic and computational complexity is required. The lecture will connect with other topics in the Computer Science and Computational Logic curriculum, such as relational databases, logic programming, and Semantic Web technologies – familiarity with these topics is not required to follow the lecture.

Schedule and Location

All sessions will take place in room APB/E005. The default arrangement is as follows:

  • The weekly lecture sessions will take place on Tuesdays from 14:50 to 16:20 and Wednesdays from 11:10 to 12:40.
  • The weekly exercise session will take place on Tuesdays from 11:10 to 12:40.


This course has first been taught at TU Dresden in the form of the 2015 lecture Foundations of Databases and Query Languages, the 2018 lecture Database Theory, and the 2019 lecture Database Theory. The plan for this year's course will be very similar.

The structure of some of the lectures of this course is inspired by the course Theory of Data and Knowledge Bases in the version given by Georg Gottlob and Thomas Lukasiewicz at the University of Oxford.

The main reference textbook for the lecture is:

  • Serge Abiteboul, Richard Hull, Victor Vianu: Foundations of Databases. Addison-Wesley. 1994.
The book is available for free from its webpage, but there are also copies in the library.

Further texts might be consulted for background information and additional details:

  • Michael Sipser: Introduction to the Theory of Computation. 2005
Accessible introduction to complexity theory that covers all topics of computational complexity that the lecture touches upon.
  • Evgeny Dantsin, Thomas Eiter, Georg Gottlob, Andrei Voronkov: Complexity and expressive power of logic programming. ACM Computing Surveys, 33:3, pp 374-425, 2001.
Covers all Datalog complexity results mentioned in the lecture. Available at (may require access from within a university network)
  • additional references will be added in the course of the lecture