Exploring PostgreSQL terminology
In order for you to understand how PostgreSQL works and follow the examples in the chapters of this book, we need to introduce the terminology used within PostgreSQL and its community of users.
PostgreSQL is a service, which means it runs as a daemon on the operating system; a running PostgreSQL daemon is called an instance. A PostgreSQL instance is often called a cluster because a single instance can serve and handle multiple databases. Every database is an isolated space where users and applications can store data.
A database is accessed by allowed users, but users connected to a database cannot cross the database boundaries and interact with data contained in another database unless they explicitly connect to the latter database too.
A database can be organized into namespaces, called schemas. A schema is a mnemonic name that the user can assign to organize database objects, such as tables, into a more structured collection. Schemas...
