Best Practices for Tuning Slow Postgres Queries | POSETTE: An Event for Postgres 2025

Post Content

Video of a conference talk where Lukas Fittl walks through what he’s learned tuning slow Postgres queries over the years. He’ll start with a quick recap of the basics (EXPLAIN ANALYZE) and then go through his iterative process of how he evaluates the root cause of a query’s slowness.

To help you identify root causes more effectively, he’ll go through common pathological Postgres planner decisions that can make a query slower than it should be and discuss when you may want to use tools like pg_hint_plan to understand alternate query plans that are available but not chosen by Postgres.

Lukas Fittl is Founder & CEO at pganalyze.com, hosted PostgreSQL Performance Monitoring, the author of pg_query (Ruby extension to parse queries using the raw_parser) and other tools. Lukas loves working with PostgreSQL statistics and visualizing them.

► Video bookmarks:

00:10 Introduction – Best Practices for Tuning Slow Postgres Queries
00:52 Debugging why a Query is Slow
02:37 Benchmarking with EXPLAIN(ANALYZE, BUFFERS)
05:41 Planner Costing & Why it Can Never be Perfect
11:32 Join Order & Parameterized Index Scans
19:30 Guiding the Planner to the Right Plan
22:27 Conclusion

Everything you need to know about POSETTE: An Event for Postgres 2025 can be found at: https://posetteconf.com

Learn more:
Watch more POSETTE talks: https://aka.ms/posette-playlist

Let’s connect:  
LinkedIn – https://www.linkedin.com/company/posetteconf/
X – @PosetteConf, https://twitter.com/PosetteConf
Mastodon – @posetteconf, https://mastodon.social/@posetteconf
Bluesky – @posetteconf.com, https://bsky.app/profile/posetteconf.com