Book Image

Mastering PostgreSQL 15 - Fifth Edition

By : Hans-Jürgen Schönig
Book Image

Mastering PostgreSQL 15 - Fifth Edition

By: Hans-Jürgen Schönig

Overview of this book

Starting with an introduction to the newly released features of PostgreSQL 15, this updated fifth edition will help you get to grips with PostgreSQL administration and how to build dynamic database solutions for enterprise apps, including designing both physical and technical aspects of the system. You'll explore advanced PostgreSQL features, such as logical replication, database clusters, advanced indexing, and user management to manage and maintain your database. You'll then work with the PostgreSQL optimizer, configure PostgreSQL for high speed, and move from Oracle to PostgreSQL. Among the other skills that the book will help you build, you’ll cover transactions, handling recursions, working with JSON and JSONB data, and setting up a Patroni cluster. It will show you how to improve performance with query optimization. You'll also focus on managing network security and work with backups and replication while exploring useful PostgreSQL extensions that optimize the performance of large databases. By the end of this PostgreSQL book, you’ll be able to use your database to its utmost capacity by implementing advanced administrative tasks with ease.
Table of Contents (16 chapters)

Improving functions

So far, you have seen how to write basic functions and triggers in various languages. Of course, many more languages are supported. Some of the most prominent ones are PL/R (R is a powerful statistics package) and PL/v8 (which is based on the Google JavaScript engine). However, those languages are beyond the scope of this chapter (regardless of their usefulness).

In this section, we will focus on improving the performance of a function. There are a few ways by which we can speed up processing:

  • Reducing the number of function calls
  • Using cached plans
  • Giving hints to the optimizer

In this section, all three of these topics will be discussed. Let’s get started with reducing the number of function calls and see how this can be done.

Reducing the number of function calls

In many cases, performance is bad because functions are called way too often. In my opinion—and I cannot stress this point enough—calling things too...