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What’s New
  • 26.Sep.2025: 10th Anniversary! This content was launched on 26 September 2015.
  • 14.Dec.2024: Added Conflicts in Section 11.2.4.
  • 13.Dec.2024: Added Replication Slots in Section 11.4.
  • 30.Nov.2024: Added Parallel Query in Section 3.7.
  • 28.Oct.2024: Added Incremental Backup in Section 10.5.

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 document are to explain how each subsystem works, and to provide the whole picture of PostgreSQL.

This document covers versions 18 and earlier.

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

This document was first published on 26 September 2015.

Contents

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 document 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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    I am using the best tools I need and I will decide what I use. I am always trying a lot of tools for better explanations.
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