Book Image

Learn PostgreSQL - Second Edition

By : Luca Ferrari, Enrico Pirozzi
1 (2)
Book Image

Learn PostgreSQL - Second Edition

1 (2)
By: Luca Ferrari, Enrico Pirozzi

Overview of this book

The latest edition of this PostgreSQL book will help you to start using PostgreSQL from absolute scratch, helping you to quickly understand the internal workings of the database. With a structured approach and practical examples, go on a journey that covers the basics, from SQL statements and how to run server-side programs, to configuring, managing, securing, and optimizing database performance. This new edition will not only help you get to grips with all the recent changes within the PostgreSQL ecosystem but will also dig deeper into concepts like partitioning and replication with a fresh set of examples. The book is also equipped with Docker images for each chapter which makes the learning experience faster and easier. Starting with the absolute basics of databases, the book sails through to advanced concepts like window functions, logging, auditing, extending the database, configuration, partitioning, and replication. It will also help you seamlessly migrate your existing database system to PostgreSQL and contains a dedicated chapter on disaster recovery. Each chapter ends with practice questions to test your learning at regular intervals. By the end of this book, you will be able to install, configure, manage, and develop applications against a PostgreSQL database.
Table of Contents (22 chapters)
20
Other Books You May Enjoy
21
Index

Understanding basic table manipulation statements

Now that you have learned how to create tables, you need to understand how to insert, view, modify, and delete data in the tables. This will help you update any incorrect entries, or update existing entries, as needed. There are a variety of commands that can be used for this, which we will look at now.

Inserting and selecting data

In this section, we will learn how to insert data into tables. To insert data into tables, you need to use the INSERT command. The INSERT command inserts new rows into a table.

It is possible to insert one or more rows specified by value expressions, or zero or more rows resulting from a query. We will now go through some use cases as follows:

  1. To insert a new user in the users table, execute the following command:
    forumdb=> insert into users (username,gecos,email) values ('myusername','mygecos','myemail');
    INSERT 0 1
    

    This result shows...