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If you are of a certain age, the words 38911 BASIC BYTES FREE will do something to you that no amount of therapy can undo. You remember the blue screen. You remember typing in three pages of a listing from a magazine, getting ?SYNTAX ERROR IN 2340, and not knowing which of the three pages contained the typo. You remember that the disk drive was device 8, and that it was slower than continental drift.

I have some news. All of that now runs inside PostgreSQL.

Yesterday, I had the pleasure of presenting at the Postgres User Group Estonia, and that was a delightful experience! Many thanks to Ervin Weber, who literally spent three years trying to make it happen. I was happy to give back to one of my favorite places in the world – the city of Tallinn.

Nested loop joins are PostgreSQL's most notorious performance disaster—but only when the planner misestimates row counts.

For PostgreSQL administrators, DBAs, SREs, and platform teams, understanding how backup data moves through a system is just as important as knowing when a backup completed successfully. Questions about repository layout, WAL handling, metadata, integrity, and recovery usually surface when troubleshooting, validating a backup strategy, or preparing for recovery.

Merge join shines when data is already sorted by an index, but stumbles when it has to pay for a sort first.

A field report on recovering core PostgreSQL tables after all database files were encrypted by ransomware and the system catalogs were unusable. With only test-environment DDL available, PDU dropscan was adapted to match individual table files against known table structures and export the critical data.

After more than 20 years working with PostgreSQL, I keep seeing the same problems surface at the worst possible times - bloat that sneaks up on you, replication slots quietly holding back WAL, transaction ID wraparound that nobody caught in time, backups that silently stopped working weeks ago. There are also data and catalog corruption issues like TOAST table corruption or a mismatch between heap state and VM state causing problems with vacuum operations. What I always wanted was a single tool I could point at any PostgreSQL instance and get a clear, actionable picture of its health.

Hot off the press: pgcopydb v0.18 is out!

It’s the biggest release the project has had — 88 commits since v0.17, which shipped in August 2024. I took a break from my Open Source responsibilities for a while, because I was lacking employer support to make it happen.

One of our client’s PostgreSQL 16.8 production databases started logging what looked like a memory error:

ERROR: invalid memory alloc request size

The error immediately pointed toward two likely suspects: 

Materialize buffers rows unconditionally; Memoize caches them by key. Same goal, opposite mechanisms—and both deserve a closer look.

Starting from a ransomware recovery case, this article explains how PostgreSQL single-file-per-relation storage can make catalog recovery especially difficult, and compares that exposure with MySQL and Oracle.

1. pgsql_tweaks is a bundle of functions and views for PostgreSQL

2. Gülçin Yıldırım Jelínek: PostgreSQL as a temporal database

   30. Juni 2026 - 18:00
   Postgres 18 introduced temporal keys (WITHOUT OVERLAPS, PERIOD).Postgres 19 expands (UPDATE/DELETE ... FOR PORTION OF) temporal capabilities further.