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CREATE ROLE

Name

CREATE ROLE -- define a new database role

Synopsis

CREATE ROLE name [ [ WITH ] option [ ... ] ]
sql-createrolesql-createrolesql-createrole
where option can be:
    
      SUPERUSER | NOSUPERUSER
    | CREATEDB | NOCREATEDB
    | CREATEROLE | NOCREATEROLE
    | CREATEUSER | NOCREATEUSER
    | INHERIT | NOINHERIT
    | LOGIN | NOLOGIN
    | CONNECTION LIMIT connlimit
    | [ ENCRYPTED | UNENCRYPTED ] PASSWORD 'password'
    | VALID UNTIL 'timestamp' 
    | IN ROLE rolename [, ...]
    | IN GROUP rolename [, ...]
    | ROLE rolename [, ...]
    | ADMIN rolename [, ...]
    | USER rolename [, ...]
    | SYSID uid 

CREATE ROLE name IDENTIFIED BY password;

Description

CREATE ROLE adds a new role to an EnterpriseDB 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 31 and Chapter 33 for information about managing users and authentication. You must have CREATEROLE privilege or be a database superuser to use this command.

Redwood compatible syntax for creating role is also available by using the IDENTIFIED BY clause. The IDENTIFIED BY clause will create a schema with the name of which the role will be the owner.

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.

CREATEUSER NOCREATEUSER

These clauses are an obsolete, but still accepted, spelling of SUPERUSER and NOSUPERUSER. Note that they are not equivalent to CREATEROLE as one might naively expect!

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 alternate spelling CREATE USER.

CONNECTION LIMIT connlimit

If role can log in, this specifies how many concurrent connections the role can make. -1 (the default) means no limit.

PASSWORD password

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.

ENCRYPTED UNENCRYPTED

These key words control whether the password is stored encrypted in the system catalogs. (If neither is specified, the default behavior is determined by the configuration parameter password_encryption.) If the presented password string is already in MD5-encrypted format, then it is stored encrypted as-is, regardless of whether ENCRYPTED or UNENCRYPTED is specified (since the system cannot decrypt the specified encrypted password string). This allows reloading of encrypted passwords during dump/restore.

Note that older clients may lack support for the MD5 authentication mechanism that is needed to work with passwords that are stored encrypted.

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 rolename

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 rolename

IN GROUP is an obsolete spelling of IN ROLE.

ROLE rolename

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 rolename

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 rolename

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 to change the attributes of a role, and DROP ROLE 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 and REVOKE.

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 before creating a database.

The INHERIT attribute is the default for reasons of backwards compatibility: in prior releases of EnterpriseDB, 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.

EnterpriseDB includes a program createuser 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.

Note that the maximum length limit for user ID and password is 63 characters.

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 rolename ]

Multiple initial administrators, and all the other options of CREATE ROLE, are EnterpriseDB 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 EnterpriseDB 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.