The view pg_roles provides access to information about database roles. This is simply a publicly readable view of pg_authid that blanks out the password field.
This view explicitly exposes the OID column of the underlying table, since that is needed to do joins to other catalogs.
Table 48-65. pg_roles Columns
|Role has superuser privileges
|Role automatically inherits privileges of roles it is a member of
|Role can create more roles
|Role can create databases
|Role can update system catalogs directly. (Even a superuser cannot do this unless this column is true)
|Role can log in. That is, this role can be given as the initial session authorization identifier
| Role is a replication role. That is, this role can initiate streaming replication (see Section 25.2.5) and set/unset the system backup mode using
|For roles that can log in, this sets maximum number of concurrent connections this role can make. -1 means no limit.
|Not the password (always reads as ********)
|Password expiry time (only used for password authentication); null if no expiration
|Role-specific defaults for run-time configuration variables
|ID of role