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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Index

Introducing extensions

SQL is a declarative language that allows you to create and manipulate objects, as well as data. You can group SQL statements into scripts so that you can run the scripts in a more predictable and reproducible way. However, such scripts are seen by PostgreSQL as a sequence of unrelated commands, that is, you are responsible for correlating such commands into appropriate scripts. Things get even worse when you have to deal with foreign programming languages (e.g., PL/Perl and other not SQL-based languages) or binary libraries; the cluster knows nothing about your aims or how the objects are related to each other. Luckily, extensions help you get order out of chaos.

An extension is a packaged set of files that can be installed in the cluster in order to provide more functionalities, that is, to “extend” the current cluster set of features. Unlike scripts, extensions are managed strictly through specific commands that install, deploy, load, and...