Book Image

Learn PostgreSQL - Second Edition

By : Luca Ferrari, Enrico Pirozzi
1 (2)
Book Image

Learn PostgreSQL - Second Edition

1 (2)
By: Luca Ferrari, Enrico Pirozzi

Overview of this book

The latest edition of this PostgreSQL book will help you to start using PostgreSQL from absolute scratch, helping you to quickly understand the internal workings of the database. With a structured approach and practical examples, go on a journey that covers the basics, from SQL statements and how to run server-side programs, to configuring, managing, securing, and optimizing database performance. This new edition will not only help you get to grips with all the recent changes within the PostgreSQL ecosystem but will also dig deeper into concepts like partitioning and replication with a fresh set of examples. The book is also equipped with Docker images for each chapter which makes the learning experience faster and easier. Starting with the absolute basics of databases, the book sails through to advanced concepts like window functions, logging, auditing, extending the database, configuration, partitioning, and replication. It will also help you seamlessly migrate your existing database system to PostgreSQL and contains a dedicated chapter on disaster recovery. Each chapter ends with practice questions to test your learning at regular intervals. By the end of this book, you will be able to install, configure, manage, and develop applications against a PostgreSQL database.
Table of Contents (22 chapters)
20
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21
Index

Summary

In this chapter, we discussed logical replication. We saw that logical replication is based on a concept of reverse engineering, starting with the analysis of WAL segments to extract the logical commands that have to be passed to a replica server. We saw that logical replication is useful when we want to replicate parts of databases and when we want to make hot migrations between different versions of PostgreSQL. Logical replication makes this possible because it does not binarily replicate data but, rather, extracts the logical DML commands from WAL files, which are then replicated on the replica server.

We saw how to make a logical replica in practice and have addressed some of the issues that can occur when we work with logical replication.

In the next chapter, we’ll talk about useful tools and extensions. We will see which tools are best to make life easier for a PostgreSQL DBA.