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In the past there have been many discussions about using UUID as a primary key in PostgreSQL. For some applications, even a BIGINT column does not have sufficient range: it is a signed 8‑byte integer with range −9,223,372,036,854,775,808 to +9,223,372,036,854,775,807. Although these values look big enough, if we think about web services that collect billions or more records daily, this number becomes less impressive.

The PostgreSQL Hacking Workshop will be taking a well-earned Christmas break in December of 2025. The future of the workshop is a little bit unclear, because I'm continuing to have a bit of trouble finding enough good talks online to justify doing one per month: the best source of talks for the event is pgconf.dev, but not all of those talks are about hacking on PostgreSQL, and not all of those that are about hacking are equally interesting to potential attendees.

Earlier this year we started a program (“Developer U”) to help colleagues who show promise for PostgreSQL Development to become contributors. Meet Bryan Green, working on the Platform Operations team at EDB, who just enjoys understanding how things work at the lowest levels.

Previously…

In our first JIT episode, we discussed how we could, using copy-patch, easily create a JIT compiler for PostgreSQL, with a slight improvement in performance compared to the PostgreSQL interpreter.

The secret to unlocking performance gains often lies not just in what you ask in a query, but in how Postgres finds the answer. The Postgres EXPLAIN system is great for understanding how data is being queried. One of secretes to reading EXPLAIN plans is understanding the type of scan done to retrieve the data. The scan type can be the difference between a lightning-fast response or a slow query.

Today I’ll break down the most common scan types, how they work, and when you’ll see them in your queries.

As a PostgreSQL-specific monitoring solution, pgwatch is mostly known for storing collected metrics in a PostgreSQL database. While great, as you probably should "just Use Postgres for everything" xD... in some scenarios and specific setups, this might be a limitation.

Retrieval-Augmented Generation (RAG) has become one of the most practical ways to give Large Language Models (LLMs) access to your own data. Rather than fine-tuning a model or hoping it somehow knows about your documentation, RAG lets you retrieve relevant content from your own sources and provide it as context to the LLM at query time. The result is accurate, grounded responses based on your actual content.In this three-part series, I'll walk through building a complete RAG server using PostgreSQL as the foundation. We'll cover:

In a PostgreSQL database, sequences provide a convenient way to generate a unique identifier, and are often used for key generation. From the community, PostgreSQL provides functions and SQL language to help manage sequence generation, but the sequences themselves are not without limitations in a multi-master environment.

The hidden cost of knowing too much. That's one way to describe what happens when your data is skewed, Postgres statistics targets are set high, and the planner tries to estimate a join. For over 20 years, Postgres used a simple O(N^2) loop to compare (equi-join) Most Common Values (MCVs) during join estimation. It worked fine when statistics targets are small (default_statistics_target defaults

PostgreSQL Belgium User Group had a new meetup on November 25, in Haasrode, Leuven, organized by Kim Jansen, An Vercammen, Boriss Mejías and Stefan Fercot.

Speakers:

• An Vercammen
• Marco Huygen
• Priyanka Mittal
• Boriss Mejías

Related blog post by Kim Jansen

© Laurenz Albe 2025

Sometimes a string column should only contain one of a limited number of distinct values. Examples would be the current state of a service request or the US state in an address. There are several ways to implement such a column in PostgreSQL, the most interesting being an enum type or a lookup table. In this article, I will explore the benefits and disadvantages of these methods.