pg_roles

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 1. pg_catalog.pg_roles
column	type	references	description
`rolname`	name		Role name
`rolsuper`	bool		Role has superuser privileges
`rolinherit`	bool		Role automatically inherits privileges of roles it is a member of
`rolcreaterole`	bool		Role may create more roles
`rolcreatedb`	bool		Role may create databases
`rolcatupdate`	bool		Role may update system catalogs directly. (Even a superuser may not do this unless this column is true.)
`rolcanlogin`	bool		Role may log in. That is, this role can be given as the initial session authorization identifier
`rolconnlimit`	int4		For roles that can log in, this sets maximum number of concurrent connections this role can make. -1 means no limit
`rolpassword`	text		Not the password (always reads as ********)
`rolvaliduntil`	timestamptz		Password expiry time (only used for password authentication); NULL if no expiration
`rolconfig`	text[]		Session defaults for run-time configuration variables
`rolresqueue`	oid	pg_resqueue.oid	Object ID of the resource queue this role is assigned to.
`oid`	oid	pg_authid.oid	Object ID of role
`rolcreaterextgpfd`	bool		Role may create readable external tables that use the gpfdist protocol.
`rolcreaterexthttp`	bool		Role may create readable external tables that use the http protocol.
`rolcreatewextgpfd`	bool		Role may create writable external tables that use the gpfdist protocol.