The pg_authid table contains information about database authorization identifiers (roles). A role subsumes the concepts of users and groups. A user is a role with the rolcanlogin flag set. Any role (with or without rolcanlogin) may have other roles as members. See pg_auth_members.

Since this catalog contains passwords, it must not be publicly readable. pg_roles is a publicly readable view on pg_authid that blanks out the password field.

Because user identities are system-wide, pg_authid is shared across all databases in a WarehousePG cluster: there is only one copy of pg_authid per system, not one per database.

column	type	references	description
oid	oid		Row identifier (hidden attribute; must be explicitly selected)
rolname	name		Role name
rolsuper	boolean		Role has superuser privileges
rolinherit	boolean		Role automatically inherits privileges of roles it is a member of
rolcreaterole	boolean		Role may create more roles
rolcreatedb	boolean		Role may create databases
rolcatupdate	boolean		Role may update system catalogs directly. (Even a superuser may not do this unless this column is true)
rolcanlogin	boolean		Role may log in. That is, this role can be given as the initial session authorization identifier
rolreplication	boolean		Role is a replication role. That is, this role can initiate streaming replication and set/unset the system backup mode using pg_start_backup and pg_stop_backup.
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		Password (possibly encrypted); NULL if none. The format depends on the form of encryption used.1
rolvaliduntil	timestamptz		Password expiry time (only used for password authentication); NULL if no expiration
rolresqueue	oid		Object ID of the associated resource queue ID in pg_resqueue
rolcreaterextgpfd	boolean		Privilege to create read external tables with the gpfdist or gpfdists protocol
rolcreaterexhttp	boolean		Privilege to create read external tables with the http protocol
rolcreatewextgpfd	boolean		Privilege to create write external tables with the gpfdist or gpfdists protocol
rolresgroup	oid		Object ID of the associated resource group ID in pg_resgroup

Notes¹:

• For an MD5-encrypted password, rolpassword column will begin with the string md5 followed by a 32-character hexadecimal MD5 hash. The MD5 hash will be of the user's password concatenated to their user name. For example, if user joe has password xyzzy WarehousePG will store the md5 hash of xyzzyjoe.

• If the password is encrypted with SCRAM-SHA-256, the rolpassword column has the format:

  SCRAM-SHA-256$<iteration count>:<salt>$<StoredKey>:<ServerKey>

  where <salt>, <StoredKey> and <ServerKey> are in Base64-encoded format. This format is the same as that specified by RFC 5803.

• If the password is encrypted with SHA-256, the rolpassword column is a 64-byte hexadecimal string prefixed with the characters sha256.

A password that does not follow any of these formats is assumed to be unencrypted.

Parent topic: System Catalogs Definitions