Book Image

Learn PostgreSQL

By : Luca Ferrari, Enrico Pirozzi
Book Image

Learn PostgreSQL

By: Luca Ferrari, Enrico Pirozzi

Overview of this book

PostgreSQL is one of the fastest-growing open source object-relational database management systems (DBMS) in the world. As well as being easy to use, it’s scalable and highly efficient. In this book, you’ll explore PostgreSQL 12 and 13 and learn how to build database solutions using it. Complete with hands-on tutorials, this guide will teach you how to achieve the right database design required for a reliable environment. You'll learn how to install and configure a PostgreSQL server and even manage users and connections. The book then progresses to key concepts of relational databases, before taking you through the Data Definition Language (DDL) and commonly used DDL commands. To build on your skills, you’ll understand how to interact with the live cluster, create database objects, and use tools to connect to the live cluster. You’ll then get to grips with creating tables, building indexes, and designing your database schema. Later, you'll explore the Data Manipulation Language (DML) and server-side programming capabilities of PostgreSQL using PL/pgSQL, before learning how to monitor, test, and troubleshoot your database application to ensure high-performance and reliability. By the end of this book, you'll be well-versed with the Postgres database and be able to set up your own PostgreSQL instance and use it to build robust solutions.
Table of Contents (27 chapters)
Section 1: Getting Started
Section 2: Interacting with the Database
Section 3: Administering the Cluster
Section 4: Replication
Section 5: The PostegreSQL Ecosystem


In this chapter, we discussed logical replication. We have seen that logical replication is based on a concept of reverse engineering that starts 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, which are then replicated on the replica server. We have seen 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 useful extensions. We will see which tools are best to make life easier for a PostgreSQL DBA.