Managing User Accounts
As a PostgreSQL administrator, you may be responsible for creating user accounts and groups. You may also be responsible for granting and revoking privileges.
In most environments, there is a one-to-one mapping between a user's operating system identity and his PostgreSQL identity. In fact, your PostgreSQL username is often identical to your OS username.
In some cases, other configurations are useful. For example, you may want most of your users to identify themselves uniquely while providing an anonymous account for low-privileged guests. You may also have a client application that identifies itself rather than identifying the user (this is useful for utility applications that can be executed by any user without providing ...