Postgres Weekly
Plus the PGConf.dev videos, fast approximations for large datasets, and Andy Pavlo joins ClickHouse.

#​660 — August 5, 2026

Web Version

Lots of videos from this year's PGConf.dev are now on YouTube and I've rounded up some highlights at the end of the issue!
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Your editor, Peter Cooper

Together with  EDB Postgres AI

Postgres Weekly

COUNT(DISTINCT) Too Slow? A Guide to Fast Approximations — A thorough, hands-on look at Postgres's powers of approximation and sampling, covering the pros, cons, and performance profiles of approaches including TABLESAMPLE, hll, and Apache DataSketches, on a 10 million row test table.

Elizabeth Garrett Christensen (Snowflake)

Model the Cost of an Oracle-To-Postgres Move — Weighing a move off Oracle? EDB's free calculator lets you model the cost by database tier and support level. Pressure-test the migration in a few minutes, before you commit to anything.

EDB sponsor

SQL Improvements in Postgres 11–18: A Personal Selection — Eight releases' worth of SQL features, picked by a longtime contributor and grouped by topic. The part on modelling band membership over time with tstzmultirange and range_agg() alone is worth a look, but there's much to enjoy.

Dimitri Fontaine

Unveiling a 13-Year-Old Postgres Bug in Cascading Replication — A guard added to streaming replication in Postgres 9.3 could lock a cascading standby out of streaming from its upstream after falling back to archive recovery. It's been fixed and will land in the next minor releases: 18.5, 17.11, and so on.

Gabriele Bartolini (EDB)

🤖 'Turning Claude into Postgres So I Can Raise a Series A' — What happens when you stick an LLM behind the Postgres wire protocol and just let it deal with queries however it wants? This, apparently. Yes, it's a bit of fun, but he really did implement actual storage APIs for it to use! 😅

Jacob Jackson

Waiting for Postgres 19: SQL Property Graph Queries (SQL/PGQ) — If you've wondered what SQL property graph queries buy you over just using normal joins, you're not alone!

Hubert depesz Lubaczewski

📄 Andy Pavlo Joins ClickHouse to Establish ClickHouse Labs"One larger question we will investigate is how DBMSs like ClickHouse and PostgreSQL fit into emerging AI and agentic technologies." Andy Pavlo (ClickHouse)

📄 Hybrid Search Patterns with Postgres and pgvector – What iterative index scans bring to the party. Christopher Winslett

📄 TDE (Transparent Data Encryption) Performance in Postgres Zsolt Parragi (Percona)

📺 THE PGCONF.DEV VIDEOS:

PGConf.dev 2026 took place in Vancouver this May, and there are a whopping 47 videos in this YouTube playlist to enjoy, if you didn't attend. Some highlights:

  • ▶️ 30 Years of PostgreSQL Retrospective with Momjian, Wieck, Chen, Lockhart, Lane and Mikheev – A panel (above) of Postgres pioneers revisits technical decisions, defining moments, and lessons from over the years. Moderated by Melanie Plageman and Jonathan Katz.

  • ▶️ What's Missing in Postgres? with Bruce Momjian – A look at 'missing' features including sharding, TDE, global indexes, and multi-master replication. The slides are available, if you prefer.

  • ▶️ Building the Next Generation of Postgres Contributors with Claire Giordano – The Talking Postgres host reflects on what it takes to get more people involved with the project.

  • ▶️ Real-Time Postgres Patch Idea Evaluation with Freund, Linnakangas, Lane, and Haas – Leading committers evaluate 'surprise patch ideas' live, with Robert Haas moderating.

  • ▶️ Why is Postgres Terrible? with Christophe Pettus – First admitting Postgres isn't terrible, Christophe nonetheless examines real-world pain points, mitigations, and opportunities for improvement.

  • ▶️ Profiling Postgres Perils with Andres Freund – A tour of misleading benchmarks, profiling traps, and counterintuitive performance results.

Alternatively, check out the playlist for anything that catches your eye – there's a lot more than just the above.

Issue 659 #660