In Chapter 10, Making Sense of Backups and Replication, our focus was on replication, transaction log shipping, and logical decoding. After looking at mostly administration-related topics, the goal now is to aim at a broader topic. In the PostgreSQL world, many things are done through extensions. The advantage of extensions is that functionality can be added without bloating the PostgreSQL core. People can choose from competing extensions and find what is best for them. The philosophy is to keep the core slim, relatively easy to maintain, and ready for the future.

In this chapter, some of the most widespread extensions for PostgreSQL will be discussed. However, before digging deeper into this issue, I want to state that this chapter only features a list of extensions that I personally find useful. There are so many modules out there these days that it is impossible to cover them all in a reasonable way. Information is published every day, and it is sometimes even hard for a professional to be aware of everything out there. New extensions are being published as we speak, and it may be a good idea to take a look at PostgreSQL Extention Network (PGXN) (https://pgxn.org/), which contains a large variety of extensions for PostgreSQL.

In this chapter, we will cover the following topics:

• Understanding how extensions work
• Making use of contrib modules
• Other useful extensions

Note that only the most important extensions will be covered.