Getting to Know Your Cluster
To be a proficient user and administrator of a PostgreSQL cluster, you first must know and understand how PostgreSQL works. A database system is a very complex beast, and PostgreSQL, being an enterprise-level Database Management System (DBMS), is in no way a simple software system. However, thanks to very good design and implementation, once you understand the basic concepts and terminology of PostgreSQL, things will quickly become comprehensive and clear.
This chapter will continue from the foundation of the previous chapter and introduce you to some other PostgreSQL terminology and concepts, as well as teaching you how to interact with the cluster. You will also be introduced to the psql client, which ships with PostgreSQL and is the recommended way to connect to your database. You are free to use any SQL client that can connect to PostgreSQL, and all the code and examples shown in this chapter will run out of the box in any other client as well, but we recommend that you take some time to learn psql. Shipped with PostgreSQL, psql is guaranteed to work in any situation and is the default way to connect to a cluster. psql is a text-only client; if you are more comfortable using a graphical client, you can have a look at pgAdmin4, one of the most famous PostgreSQL graphical clients.
This chapter covers the following main topics:
- Managing your cluster
- Connecting to the cluster
- Exploring the disk layout of PGDATA
- Exploring configuration files and parameters
