Extensions are the PostgreSQL packages that allow a database to be improved by installing new types, code, and functionalities. The main advantage of these packages is that each one is managed as a whole, without any regard as to how much data and functionality it installs into the database. This makes extensions very easy to manage, maintain, and even upgrade, thanks to a well-defined standard for upgrade paths.

The PostgreSQL Extension ecosystem is continuously growing and, thanks to the PGXN, developers and administrators can find and contribute the extensions they need. Using tools such as pgxnclient, it is also possible to automate the extension management.

The next chapter will focus on processes, showing you how to make backend (connection) processes to share events and data and how to make them communicate with external applications. We will also look at how to...