Query Optimization



Query optimization is addressed shortly in Database Systems, this lecture looks at a broader topic of optimization techniques. It concentrates on the central issues like join ordering and access path selections, but gives an overview of the whole query processing machinery. The main goals of the lecture are twofold: First, to learn different optimization techniques, which are also relevant in other areas. And second, to get an understanding how queries are processed and why queries are fast or slow.


  • Lecture: Wednesdays, 8:15 - 9:45 am in MI HS2
  • Exercise: Fridays, 2:15 - 3:45 pm in MI HS2
There are no recordings. Livestream may work, but we make no guarantees. Attendance is strongly recommended.


The uploaded slides might change from time to time, so make sure to load the most recent version each week. Slides


Exercise sheets will be distributed through moodle

see gitlab and mattermost
Uni Schema


Date: TBA
There will be no retake exam.


  • J.D. Ullman. Database and Knowledge Base Systems. Computer Science Press, 1989.
  • T. Özsu and J. Blakeley. Modern Database Systems. Addison Wesley, 1995.
  • H. Garcia-Molina and J.D. Ullman and J. Widom. Database System Implementation. Prentice Hall, 1999.
  • P. Gassner, G. Lohman, and K. Schiefer. Query optimization in the IBM DB2 family. IEEE Data Engineering Bulletin, 16:4 18, Dec. 1993.
  • S. Chaudhuri. An Overview of Query Optimization in Relational Systems. PODS, 1998
  • G. Moerkotte. Building Query Compilers. (draft)