This book covers learning how to create SQL queries using a PostgreSQL database. If you have been looking for a book that has easy to understand step-by-step instructions and screen shots that show you how to create queries from data stored in a Windows PostgreSQL database, this is the book for you. This book has been designed to have you creating queries quickly, by teaching you the basics and more. It is written from the perspective that you have not created queries using PostgreSQL.
Most companies would find it helpful if they had employees, that could create queries to answer business needs. In my 25+ years of experience, I have noticed that few, if any people outside of the IT department have SQL skills. If that sounds like you, this book will teach you how to create SQL queries. This book is not just for people already in IT. While this book is designed for SQL beginners, it is also helpful for Data Analysts, Engineers and Scientists.
To help you become familiar with the syntax and features of SQL, this book contains over 465 illustrations that provide a visual tour of the results of the queries that you create. There are over 345 ready to use queries in the examples and exercises in this book, that you can use to create queries on your own.
This book will show you how to use some of the most used SQL keywords, operators and functions, by completing the hands on exercises. This book will get you up and running quickly, by teaching the basics of creating queries and a little more, so that you can use PostgreSQL to create the queries that you need.
You will learn how to:
- Create queries that use several operators and functions
- Filter data, to retrieve just the data that you need
- Sort and group data
- Join tables so that data from more than one table can be retrieved at the same time
- Create subqueries and more
In today's work environment, being able to create queries that can be used to analyze the data, will give you an edge over other people. SQL isn't just for the IT department anymore. After completing the exercises in this book, you will be able to create queries that answer questions like the ones listed below.
- What are the yearly sales by region?
- What are the top 10 selling products, based on the quantity sold?
- How many customers in California placed orders in 2018?
If you need to learn how to create SQL queries using T-SQL/SQL Server, see ISBN 978-1-935208-44-0.
If you need to learn how to create SQL queries using MySQL, see ISBN 978-1-935208-45-7.
If you need to learn how to create SQL queries using an SQLite database, see ISBN 978-1-935208-46-4.
If you need to learn how to create SQL queries using Oracle SQL, see ISBN 978-1-935208-48-8.
If you already know some SQL, but want to get more practice, my Big Book Of SQL Queries (ISBN 978-1-935208-49-5), has over 250 practice queries that you can use to create queries in any of the following versions of SQL: T-SQL/SQL Server, MySQL, SQLite, PostgreSQL or Oracle.
