The Future of Plan Management and Feedback Loops
October 20–23
Historically, Postgres has treated bad query plans as planner bugs to be reported and fixed, rather than teaching people to pin a particular plan. But even when a fix lands in a future release, a production system today is still suffering from the bad plan.
With Postgres 19, this perspective has shifted: pg_plan_advice gives us a new ability to control query plans and repeat a plan we've seen before. We'll start with an overview of how pg_plan_advice enables plan control, and how combining it with the pg_stat_plans extension lets us capture plan advice strings for all executed plans in aggregate.
We'll then discuss how far this gets us toward basic plan management, what is still missing, and evaluate feedback loops as an alternative to full plan control, e.g. informing the planner about past mis-estimates so future planning avoids repeating a bad plan.
We'll conclude by reviewing how external tools like pganalyze can integrate with plan management in Postgres, and how a work
