The San Francisco Bay Area PostgreSQL Meetup Group Message Board › New Meetup: Statistics and Postgres - How the planner sees your data.

New Meetup: Statistics and Postgres - How the planner sees your data.

David Fetter
user 2674386
Group Organizer
Oakland, CA
Send an Email Post a Greeting
Announcing a new Meetup for The San Francisco Bay Area PostgreSQL Meetup Group!

What: Statistics and Postgres - How the planner sees your data.

When: September 8, 2009 7:00 PM

Where: East Bay, likely at UC Berkeley

Nathan Boley presents:

Statistics and Postgres - How the planner sees your data.

Postgres relies heavily on statistics collected from data tables to
execute queries in the most efficient way possible. Despite the
relative simplicity of these statistics, the actual process by which
they are collected and used to generate plans is a bit enigmatic. In
the next 50 minutes, I will go through the assumptions that the
planner makes about data access patterns, the heuristics that generate
and apply the summary statistics, and a theorem from probability
theory that is central to the planner's estimates. Finally, if time
permits, I will show how a custom selectivity function can
dramatically improve the planner accuracy for odd data distributions.
My hope is that a clear understanding of the process by which Postgres
collects and applies statistics will remove some of the black magic
from tuning Postgres and spur the development of better analysis
techniques.

Learn more here:
http://postgresql.mee...­
Powered by mvnForum

People in this
Meetup are also in:

Log in

Not registered with us yet?

Sign up

Meetup members, Log in

By clicking "Sign up" or "Sign up using Facebook", you confirm that you accept our Terms of Service & Privacy Policy