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

Execution of a statement

SQL is a declarative language: you ask the database to execute something on the data it contains, but you do not specify how the database is supposed to complete the SQL statement. For instance, when you ask to get back some data, you execute a SELECT statement, but you only specify the clauses that specify which subset of data you need, not how the database is supposed to pull the data from its persistent storage. You have to trust the database – in particular, PostgreSQL – to be able to do its job and get you the fastest path to the data, always, under any circumstance of workload. The good news is that PostgreSQL is really good at doing this and is able to understand (and to some extent, interpret) your SQL statements and its current workload to provide you with access to the data in the fastest way.

However, finding the fastest path to the data often requires an equilibrium between searching for the absolute fastest path and the time spent in...