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

Advanced statistics with pg_stat_statements

While the PostgreSQL statistics collector is rich and mature, having to monitor connection activity can be a little tricky since the pg_stat_activity catalog does not provide historic information. For example, as we explained previously, there will be a single tuple with the last executed statement, so no history nor extended details will be provided.

The pg_stat_statements extension solves this problem by providing a single view that gives you a full history of executed statements, timing, and other little details that can come in very handy when doing introspection. Moreover, pg_stat_statements provides a count of how many times the same statement has been executed, resulting in important information that queries might need to pay attention to for optimization purposes.

In the following subsections, you will learn how to install this extension and use it.

Installing the pg_stat_statements extension

This extension is shipped with PostgreSQL...