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 basic concepts

In PostgreSQL, there are two kinds of replication techniques:

  • Asynchronous replication: In asynchronous replication, the primary device (source) sends a continuous flow of data to the secondary one (target), without receiving any return code from the target. This type of copying has the advantage of speed, but it brings with it greater risks of data loss because the received data is not checked.
  • Synchronous replication: In synchronous replication, a source sends the data to a target, that is, the second server; at this point, the server sends back a code to verify the correctness of the data. If the check is successful, the transfer is completed.

Both methods have advantages and disadvantages, and in the Managing streaming replication section of this chapter, we will analyze them.


Let's briefly summarize what we saw in the chapter on MVCC and WAL: in that chapter, we saw how PostgreSQL stores data on disk using WAL; as we saw in Chapter 11, Transactions...