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
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21
Index

Summary

Hopefully, this chapter was full of interesting ideas for the developer and the DBA. In this chapter, we talked about complex queries; we then saw the SELECT statement and the use of the LIKE, ILIKE, DISTINCT, OFFSET, LIMIT, IN, and NOT IN clauses. We then started talking about aggregates through the GROUP BY and HAVING clauses, and we introduced some aggregate functions, such as SUM(), COUNT(), AVG(), MIN(), and MAX().

We then talked in depth about subqueries and joins. Another very interesting set of topics covered in this chapter was the UNION, EXCEPT, and INTERSECT queries. Finally, by looking at the advanced options for the INSERT, DELETE, UPDATE, and MERGE instructions, and by covering CTEs, we gave you an idea of the power of the SQL language owned by PostgreSQL.

As for the concept of aggregates, in the next chapter, we will see a new way to make aggregates using window functions. Through the use of window functions, we will see that we are able to create all...