Luca Ferrari <fluca1978@xxxxxxxxxxx> writes: >> src/backend/optimizer/README > I've read this yesterday, very interesting, but I'm looking for something > similar related to geqo. I mean, is there any presentation/demo that > step-y-step explains how geqo could take decisions? There's not a lot, but I just made a few improvements here and here: http://developer.postgresql.org/pgdocs/postgres/planner-optimizer.html http://developer.postgresql.org/pgdocs/postgres/geqo-pg-intro.html Beyond that, the GEQO chapter provides several references, and IMHO you should not be all that resistant to looking into the source code. Even if you don't read C well, many of the files provide a wealth of info in the comments. regards, tom lane