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 declarative partitioning

In this section, we will talk about declarative partitioning. It is available in PostgreSQL starting from version 10, but it is best in version 12 in terms of features and performance. We will now look at an example of partitioning by range and an example of partitioning by list.

List partitioning

In the first example of declarative partitioning, we will use the same example as we looked at when we introduced partitioning using inheritance. We will see that things become much simpler using the declarative partitioning method:

  1. First of all, let's drop the parent table and its child tables that we made previously:
DROP TABLE IF EXISTS part_tags cascade;
  1. Now let's recreate the same tables using the declarative method. First, we must define our parent table:
CREATE TABLE part_tags (
pk INTEGER NOT NULL DEFAULT nextval('part_tags_pk_seq') ,
primary key (pk,level)