In this chapter you learned how PostgreSQL manages configuration through a main text file, postgresql.conf, that can be split into smaller pieces, depending on your needs. Every configuration option can be edited in the configuration file and can be inspected within the database thanks to dedicated system catalogs. This allows the database administrator to not only have a clear understanding of the currently running configuration but to also search for configuration errors and incorrectly loaded settings.
PostgreSQL also collects statistics; that is, runtime data that was gathered during the cluster's operational time. Those statistics can help an administrator understand what is going on, or what happened in the past, in the cluster. Thanks to a different set of catalogs, which was exposed in this chapter, you learned how to dig into the details of all the information that PostgreSQL has collected for you. Being able to track and analyze what single applications, users...
