Neues vom PostgreSQL Planet

You know I had to do it as soon as I found it was possible. Yes, I installed and enabled AI in the DBeaver Query Editor so I can use AI with my PostgreSQL database work. Let’s face it. It was inevitable. However, the setup isn’t intuitive. Setting Up in DBeaver I’m going to assume […]

The post AI in the DBeaver Query Editor appeared first on Grant Fritchey.

On 8th of April 2025, Daniel Gustafsson committed patch: Add function to get memory context stats for processes   This adds a function for retrieving memory context statistics and information from backends as well as auxiliary processes. The intended usecase is cluster debugging when under memory pressure or unanticipated memory usage characteristics.

This blog posting is part of a series about organizing Meetups. While mostly centered around PostgreSQL Meetups, large parts can be adapted by other Meetups as well. All postings in this series: Checklist for Meetup Attendees (this posting) Checklist for Meetup Speakers Checklist for Meetup Organizers Overview posting Attending an in-person Meetup You found an interesting Meetup, and like to sign up. Before you sign up, please read the entire Meetup description.

This blog posting is part of a series about organizing Meetups. While mostly centered around PostgreSQL Meetups, large parts can be adapted by other Meetups as well. All postings in this series: Checklist for Meetup Attendees Checklist for Meetup Speakers Checklist for Meetup Organizers (this posting) Overview posting You are organizing a Meetup. Congratulations, this is big! Here are some recommendations: First things first: find a date. Pay attention to school holidays and public holidays, especially for in-person Meetups.

This blog posting is part of a series about organizing Meetups. While mostly centered around PostgreSQL Meetups, large parts can be adapted by other Meetups as well. All postings in this series: Checklist for Meetup Attendees Checklist for Meetup Speakers (this posting) Checklist for Meetup Organizers Overview posting You are speaking at a Meetup. Congratulations! General advice Check your slides for a good contrast, and fonts large enough.

A few days ago, I wrote about a surprising planner behavior with CTEs, DELETE, and LIMIT in PostgreSQL, a piece I hastily put together on a bus ride. That post clearly only scratched the surface of a deeper issue that I’ve since spent way too many hours exploring. So here are some more formed thoughts and findings. The core issue revisited Let’s quickly recap: when using a query like the following, the planner might execute your query in ways you don’t expect.

Greetings!

Fault tolerance is a very important aspect of every non-startup application.
It can be described as a definition:

Fault tolerance is the ability of a system to maintain proper operation despite failures or faults in one or more of its components.

But this gives only slight overview - fault tolerance concerns many areas especially when we are talking about software engineering:

I have just completed the first draft of the Postgres 18 release notes. It includes a little developer community feedback but still needs more XML markup and links.

Slides and transcript from my talk, "Anatomy of a Database Operation", at DjangoCon Europe in Dublin on 25 April 2025.

I'll share the recording as soon as it's available.

On April 23, we hosted the fourth of five (5) virtual Mini-Summits that lead up to the big one at the Postgres Development Conference (PGConf.dev), taking place May 13-16, in Montreál, Canada.

On 7th of April 2025, Álvaro Herrera committed patch: Allow NOT NULL constraints to be added as NOT VALID   This allows them to be added without scanning the table, and validating them afterwards without holding access exclusive lock on the table after any violating rows have been deleted or fixed.   Doing ALTER TABLE … Continue reading "Waiting for PostgreSQL 18 – Allow NOT NULL constraints to be added as NOT VALID"

 I am (slowly) adding handy PostgreSQL queries to my GitHub, and Vacuum is the newest category.  The end goal is to have a compilation of queries for those of us who need to keep an instance healthy.

Over the years, I have collected hundreds of various queries and hate hunting them down in my code snippet library. Finally, they will be in one place and easy to search. 

Please contribute if you have similar or better queries (hint, hint!).

Introduction

Recently, we had a long discussion in our internal chat about the concept of Trusted Extensions in PostgreSQL. It became clear that while the feature is very useful, it’s often misunderstood — especially by beginners. Let's fix that!

This post explains what trusted extensions are, why they exist, how they work, and provides some important hints and warnings for everyday use.

I recently discovered an unexpected behavior in PostgreSQL involving a pattern of using a Common Table Expression (CTE) with DELETE ... RETURNING and LIMIT to process a batch of items from a queue-like table. What seemed straightforward turned out to have a surprising interaction with the query planner. The scenario Let’s say you have a task_queue table and want to pull exactly one task for a specific queue_group_id. A common approach is using a CTE:

In the previous blog post we have seen how plenty of ram doesn’t necessary results in a faster instance.

This time we’ll quickly see how PostgreSQL and Linux relate to each other in particular if we want to run our RDBMS at scale.

Then we’ll have a look to the virtual memory in Linux and how to make it more friendly to PostgreSQL.

Let’s dig in.

We did it!

Thank you so much to everyone who made this event a success! Starting with the great talks selection (thank you, CfP committee!), to our amazing sponsors (thank you, Pat Wright!), to volunteers, to attendees!

My highlights were having multiple new speakers, new topics, and seeing a lot of new attendees for many of whom this was their first Postgres conference! I hope you all enjoyed it, and I hope to see you again!

© Laurenz Albe 2025

PostgreSQL is famous for its stability, and rightly so. But that does not mean that it can never crash. And while PostgreSQL usually cleans up after itself, it has no good way to do so after a crash (after all, it has lost its memory). As a consequence, you can end up with orphaned files in your data directory. If these files are small, they probably won't worry you. But sometimes you can end up with a lot of junk in your data directory. It is notoriously difficult to deal with that problem, so I decided to write about it.

Back in 2022, we covered how to log database query generation information from a web app using pg_stat_statements for Postgres. https://andyatkinson.com/blog/2022/10/07/pgsqlphriday-2-truths-lie

The application context annotations can look like this. They’ve been re-formatted for printing:

We continue to follow the news about PostgreSQL 18. The January CommitFest brings in some notable improvements to monitoring, as well as other new features.

You can find previous reviews of PostgreSQL 18 CommitFests here: 2024-07, 2024-09, 2024-11.

Reviews of the extension search path patch, now committed and slated for PostgreSQL 18, revealed a few issues with extension configuration. Based on the ensuing discussion, and even though PostgreSQL 18 will include workarounds, it’s best to make adjustments to the extensions you maintain, the better to serve existing PostgreSQL versions and to hew closer to best practices.

Thus, a couple of recommendations for extension maintainers.