Nordic PGDay 2026 in the Happiest Country in the World

On March 24, I had the pleasure of attending and speaking at Nordic PGDay 2026. This year, the PostgreSQL community gathered at the Scandic Park Hotel in Helsinki, Finland, for the 11th edition of the conference. The event was fully sold out and, for the first time, was organized as a two-track conference.

There is a special kind of magic in visiting Finland, a nation repeatedly ranked as the happiest country in the world. From the moment we arrived at the Scandic Park Hotel, it was clear that this reputation extended to the PostgreSQL community as well. The overall atmosphere was exceptionally positive, welcoming, and constructive. And the magic began even before the conference doors opened. On the evening before the event, the Helsinki skies treated us to a beautiful display of the aurora borealis — a truly unforgettable welcome and a fitting prelude to this stellar conference.

My Talk: Beyond work_mem Myths

I had the privilege of representing credativ on stage with my talk, Beyond work_mem Myths: A Source-Code-Guided Tour Through PostgreSQL Memory Usage. In the talk, I explained how PostgreSQL memory management at the connection level is frequently misunderstood, and how work_mem should be viewed as a soft limit that can be exceeded multiple times even during seemingly simple operations. Using measurements based on Linux smaps kernel interface data collected during the execution of different queries, I demonstrated that the amount of memory consumed by a single backend process can be significantly higher than the configured and expected work_mem value.

Highlights from the Schedule

The schedule was packed with high-quality technical content, covering everything from operational challenges at scale to emerging AI use cases. While it was difficult to choose between the parallel tracks, here are some of the talks that stood out to me.

• Unlock AI Agents with PostgreSQL (Mats Berglin & Miguel Toscano): In the era of AI agents, data serves as the bridge between generic LLMs and unique, context-aware experiences. The talk explained vector search at scale, specifically how the ScaNN algorithm can deliver strong performance with lower resource overhead.
• Efficiently approximating/estimating percentiles and histograms (Tomas Vondra): Tomas delivered a highly technical and insightful session on approximation algorithms. It was an excellent deep dive into how statistical insights can be gathered efficiently without severely impacting performance.
• Why Postgres Won (Gianni Ciolli): PostgreSQL is today one of the most common choices for transactional workloads, for a number of reasons. This talk explored at least one of those reasons by examining MVCC and VACUUM, topics frequently discussed within the PostgreSQL community.
• A PostgreSQL Journey – What We Learned Migrating Between 3 Platforms (James McDonald & Nina Angelvik): Database migrations are rarely just about moving data. The speakers shared their experiences from two major PostgreSQL migrations within the same organization. Each migration solved real problems, but also exposed new challenges related to performance, operational practices, developer behavior, and organizational processes.

Looking Ahead

Nordic PGDay 2026 was an excellent conference. Between the stunning northern lights, the welcoming atmosphere, the flawless organization, and the high level of technical discussion, it was an event I will not soon forget. I am already looking forward to meeting the community again at Nordic PGDay 2027.

All photos (c) Nordic PGDay organizers