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

Exploring logical replication setup

Let's explore now how to perform logical replication. In this section, we will prepare the environment we need to be able to perform our logical replication.

Logical replication environment settings

Suppose we have two machines that we will call pg1 and pg2. We must remember to set our internal DNS, or the /etc hosts file, so that pg1 can reach pg2; for example, for the pg1 server, the master server will have an IP of, and for the pg2 server, the replica server will have an IP of

First of all, let's check whether there is a connection between the two servers:

pg1:~$ ping pg2
PING ( 56(84) bytes of data.
64 bytes from ( icmp_seq=1 ttl=64 time=0.893 ms
64 bytes from ( icmp_seq=2 ttl=64 time=0.639 ms

pg2:~$ ping pg1
64 bytes from ( icmp_seq=1 ttl=64 time=1.40 ms
64 bytes from pg1...