The Internals of PostgreSQL

2026-11-03T21:51:06+00:00

I am officially open to new international opportunities! 🌍

After a temporary stay in Japan to focus on my health and personal responsibilities, I am fully recovered, ready, and excited to work abroad again.

I am highly interested in returning to Europe, as well as opportunities in the Southern Hemisphere and Southeast Asia.

Looking for:

Challenging tasks in PostgreSQL.
Roles offering international visa sponsorship OR Remote work that supports a digital nomad lifestyle.

If your team is hiring, let’s connect! Please feel free to reach out via e-Mail(hironobu @ interdb.jp or interdb.mx @ gmail.com) or DM.

What’s New

26 Sep 2026: 11th Anniversary! This content was launched on 26 September 2015.
28 Jun 2026: Section 8.5, “Asynchronous I/O in PostgreSQL” Published.
1 May 2026: Chapter 12, “Logical Replication” (Beta Version) Published.
14 Dec 2024: Added Conflicts in Section 11.2.4.

Change History (since 3rd June, 2018)

The Internals of PostgreSQL

PostgreSQL is a well-designed, open-source multi-purpose relational database system which is widely used throughout the world.

It is one huge system with the integrated subsystems, each of which has a particular complex feature and works cooperatively with each other. Although understanding of the internal mechanism is crucial for both administration and integration using PostgreSQL, its hugeness and complexity make it difficult.

The main purposes of this documentation are to explain how each subsystem works, and to provide the whole picture of PostgreSQL.

This documentation covers versions 19-beta (excluding the new buffer page lock mechanism) and earlier.

Some academic papers have referred to this documentation. The Chinese version of this documentation was published in June 2019.

This documentation was first published on 26 September 2015.

Contents

Chapter 1. Database Cluster, Databases and Tables
Chapter 2. Process and Memory Architecture
Chapter 3. Query Processing
Chapter 4. Foreign Data Wrappers (FDW)
Chapter 5. Concurrency Control
Chapter 6. VACUUM Processing
Chapter 7. Heap Only Tuple (HOT) and Index-Only Scans
Chapter 8. Buffer Manager
Chapter 9. Write-Ahead Logging (WAL)
Chapter 10. Online Backup and Point-In-Time Recovery (PITR)
Chapter 11. Streaming Replication\
Chapter 12. Logical Replication (Beta Version)

Hironobu SUZUKI

I am a software programmer/engineer, the author of:

I graduated from graduate school in information engineering (M.S. in Information Engineering), have worked for several companies as a software developer and technical manager/director. I published seven books in the fields of database and system integration (4 PostgreSQL books and 3 MySQL books). In June 2019, the Chinese book of this documentation was published.

As a director of the Japan PostgreSQL Users Group (2010-2016), I organized the largest (non-commercial) technical seminar/lecture on PostgreSQL in Japan for more than six years, and also served as the program committee chair of the Japan PostgreSQL Conference in 2013 and as a member in 2008 and 2009.

In June 2022, my interview article was published in “PostgreSQL person of the week”.

Cuando era joven, vivió en Sudamérica por unos años. Recientemente, a veces vuelve a allí.

I am seeking a remote position focused on the application of ML and AI technologies to DBMS. For personal reasons, I will be living in Japan for several years.

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