Hans-Jürgen Schönig has written various books dealing with PostgreSQL and he has been in professional PostgreSQL business (https://www.cybertec-postgresql.com) since the year 2000. We provide PostgreSQL services along with training and PostgreSQL related services.
The PostgreSQL optimizer is one of those things everybody talks about
but nobody really understands.
Therefore the goal of this talk is to outline some of the basic
concepts, explain the inner workings and provide some insights into how
things can be used to improve performance big time.