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CREATE ROLE(7) PostgreSQL 12.3 Documentation CREATE ROLE(7)
NAME
CREATE_ROLE - define a new database role
SYNOPSIS
CREATE ROLE name [ [ WITH ] option [ ... ] ]
where option can be:
SUPERUSER | NOSUPERUSER
| CREATEDB | NOCREATEDB
| CREATEROLE | NOCREATEROLE
| INHERIT | NOINHERIT
| LOGIN | NOLOGIN
| REPLICATION | NOREPLICATION
| BYPASSRLS | NOBYPASSRLS
| CONNECTION LIMIT connlimit
| [ ENCRYPTED ] PASSWORD 'password' | PASSWORD NULL
| VALID UNTIL 'timestamp'
| IN ROLE role_name [, ...]
| IN GROUP role_name [, ...]
| ROLE role_name [, ...]
| ADMIN role_name [, ...]
| USER role_name [, ...]
| SYSID uid
DESCRIPTION
CREATE ROLE adds a new role to a PostgreSQL database cluster. A role is an entity that can
own database objects and have database privileges; a role can be considered a “user”, a
“group”, or both depending on how it is used. Refer to Chapter 21 and Chapter 20 for
information about managing users and authentication. You must have CREATEROLE privilege or
be a database superuser to use this command.
Note that roles are defined at the database cluster level, and so are valid in all
databases in the cluster.
PARAMETERS
name
The name of the new role.
SUPERUSER
NOSUPERUSER
These clauses determine whether the new role is a “superuser”, who can override all
access restrictions within the database. Superuser status is dangerous and should be
used only when really needed. You must yourself be a superuser to create a new
superuser. If not specified, NOSUPERUSER is the default.
CREATEDB
NOCREATEDB
These clauses define a role's ability to create databases. If CREATEDB is specified,
the role being defined will be allowed to create new databases. Specifying NOCREATEDB
will deny a role the ability to create databases. If not specified, NOCREATEDB is the
default.
CREATEROLE
NOCREATEROLE
These clauses determine whether a role will be permitted to create new roles (that is,
execute CREATE ROLE). A role with CREATEROLE privilege can also alter and drop other
roles. If not specified, NOCREATEROLE is the default.
INHERIT
NOINHERIT
These clauses determine whether a role “inherits” the privileges of roles it is a
member of. A role with the INHERIT attribute can automatically use whatever database
privileges have been granted to all roles it is directly or indirectly a member of.
Without INHERIT, membership in another role only grants the ability to SET ROLE to
that other role; the privileges of the other role are only available after having done
so. If not specified, INHERIT is the default.
LOGIN
NOLOGIN
These clauses determine whether a role is allowed to log in; that is, whether the role
can be given as the initial session authorization name during client connection. A
role having the LOGIN attribute can be thought of as a user. Roles without this
attribute are useful for managing database privileges, but are not users in the usual
sense of the word. If not specified, NOLOGIN is the default, except when CREATE ROLE
is invoked through its alternative spelling CREATE USER (CREATE_USER(7)).
REPLICATION
NOREPLICATION
These clauses determine whether a role is a replication role. A role must have this
attribute (or be a superuser) in order to be able to connect to the server in
replication mode (physical or logical replication) and in order to be able to create
or drop replication slots. A role having the REPLICATION attribute is a very highly
privileged role, and should only be used on roles actually used for replication. If
not specified, NOREPLICATION is the default.
BYPASSRLS
NOBYPASSRLS
These clauses determine whether a role bypasses every row-level security (RLS) policy.
NOBYPASSRLS is the default. Note that pg_dump will set row_security to OFF by default,
to ensure all contents of a table are dumped out. If the user running pg_dump does not
have appropriate permissions, an error will be returned. The superuser and owner of
the table being dumped always bypass RLS.
CONNECTION LIMIT connlimit
If role can log in, this specifies how many concurrent connections the role can make.
-1 (the default) means no limit. Note that only normal connections are counted towards
this limit. Neither prepared transactions nor background worker connections are
counted towards this limit.
[ ENCRYPTED ] PASSWORD 'password'
PASSWORD NULL
Sets the role's password. (A password is only of use for roles having the LOGIN
attribute, but you can nonetheless define one for roles without it.) If you do not
plan to use password authentication you can omit this option. If no password is
specified, the password will be set to null and password authentication will always
fail for that user. A null password can optionally be written explicitly as PASSWORD
NULL.
Note
Specifying an empty string will also set the password to null, but that was not
the case before PostgreSQL version 10. In earlier versions, an empty string could
be used, or not, depending on the authentication method and the exact version, and
libpq would refuse to use it in any case. To avoid the ambiguity, specifying an
empty string should be avoided.
The password is always stored encrypted in the system catalogs. The ENCRYPTED keyword
has no effect, but is accepted for backwards compatibility. The method of encryption
is determined by the configuration parameter password_encryption. If the presented
password string is already in MD5-encrypted or SCRAM-encrypted format, then it is
stored as-is regardless of password_encryption (since the system cannot decrypt the
specified encrypted password string, to encrypt it in a different format). This allows
reloading of encrypted passwords during dump/restore.
VALID UNTIL 'timestamp'
The VALID UNTIL clause sets a date and time after which the role's password is no
longer valid. If this clause is omitted the password will be valid for all time.
IN ROLE role_name
The IN ROLE clause lists one or more existing roles to which the new role will be
immediately added as a new member. (Note that there is no option to add the new role
as an administrator; use a separate GRANT command to do that.)
IN GROUP role_name
IN GROUP is an obsolete spelling of IN ROLE.
ROLE role_name
The ROLE clause lists one or more existing roles which are automatically added as
members of the new role. (This in effect makes the new role a “group”.)
ADMIN role_name
The ADMIN clause is like ROLE, but the named roles are added to the new role WITH
ADMIN OPTION, giving them the right to grant membership in this role to others.
USER role_name
The USER clause is an obsolete spelling of the ROLE clause.
SYSID uid
The SYSID clause is ignored, but is accepted for backwards compatibility.
NOTES
Use ALTER ROLE (ALTER_ROLE(7)) to change the attributes of a role, and DROP ROLE
(DROP_ROLE(7)) to remove a role. All the attributes specified by CREATE ROLE can be
modified by later ALTER ROLE commands.
The preferred way to add and remove members of roles that are being used as groups is to
use GRANT(7) and REVOKE(7).
The VALID UNTIL clause defines an expiration time for a password only, not for the role
per se. In particular, the expiration time is not enforced when logging in using a
non-password-based authentication method.
The INHERIT attribute governs inheritance of grantable privileges (that is, access
privileges for database objects and role memberships). It does not apply to the special
role attributes set by CREATE ROLE and ALTER ROLE. For example, being a member of a role
with CREATEDB privilege does not immediately grant the ability to create databases, even
if INHERIT is set; it would be necessary to become that role via SET ROLE (SET_ROLE(7))
before creating a database.
The INHERIT attribute is the default for reasons of backwards compatibility: in prior
releases of PostgreSQL, users always had access to all privileges of groups they were
members of. However, NOINHERIT provides a closer match to the semantics specified in the
SQL standard.
Be careful with the CREATEROLE privilege. There is no concept of inheritance for the
privileges of a CREATEROLE-role. That means that even if a role does not have a certain
privilege but is allowed to create other roles, it can easily create another role with
different privileges than its own (except for creating roles with superuser privileges).
For example, if the role “user” has the CREATEROLE privilege but not the CREATEDB
privilege, nonetheless it can create a new role with the CREATEDB privilege. Therefore,
regard roles that have the CREATEROLE privilege as almost-superuser-roles.
PostgreSQL includes a program createuser(1) that has the same functionality as CREATE ROLE
(in fact, it calls this command) but can be run from the command shell.
The CONNECTION LIMIT option is only enforced approximately; if two new sessions start at
about the same time when just one connection “slot” remains for the role, it is possible
that both will fail. Also, the limit is never enforced for superusers.
Caution must be exercised when specifying an unencrypted password with this command. The
password will be transmitted to the server in cleartext, and it might also be logged in
the client's command history or the server log. The command createuser(1), however,
transmits the password encrypted. Also, psql(1) contains a command \password that can be
used to safely change the password later.
EXAMPLES
Create a role that can log in, but don't give it a password:
CREATE ROLE jonathan LOGIN;
Create a role with a password:
CREATE USER davide WITH PASSWORD 'jw8s0F4';
(CREATE USER is the same as CREATE ROLE except that it implies LOGIN.)
Create a role with a password that is valid until the end of 2004. After one second has
ticked in 2005, the password is no longer valid.
CREATE ROLE miriam WITH LOGIN PASSWORD 'jw8s0F4' VALID UNTIL '2005-01-01';
Create a role that can create databases and manage roles:
CREATE ROLE admin WITH CREATEDB CREATEROLE;
COMPATIBILITY
The CREATE ROLE statement is in the SQL standard, but the standard only requires the
syntax
CREATE ROLE name [ WITH ADMIN role_name ]
Multiple initial administrators, and all the other options of CREATE ROLE, are PostgreSQL
extensions.
The SQL standard defines the concepts of users and roles, but it regards them as distinct
concepts and leaves all commands defining users to be specified by each database
implementation. In PostgreSQL we have chosen to unify users and roles into a single kind
of entity. Roles therefore have many more optional attributes than they do in the
standard.
The behavior specified by the SQL standard is most closely approximated by giving users
the NOINHERIT attribute, while roles are given the INHERIT attribute.
SEE ALSO
SET ROLE (SET_ROLE(7)), ALTER ROLE (ALTER_ROLE(7)), DROP ROLE (DROP_ROLE(7)), GRANT(7),
REVOKE(7), createuser(1)
PostgreSQL 12.3 2020 CREATE ROLE(7)
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