ALTER ROLE (An SQL command for modifying a database role)

• https://pgpedia.info/a/alter-role.html

Description

ALTER ROLE is a DDL command for modifying a database role.

ALTER ROLE was added in PostgreSQL 8.1, superseding ALTER USER (which has been retained as an alias).

Description

• https://www.postgresql.org/docs/current/sql-alterrole.html

ALTER ROLE changes the attributes of a PostgreSQL role.

The first variant of this command listed in the synopsis can change many of the role attributes that can be specified in CREATE ROLE.

(All the possible attributes are covered, except that there are no options for adding or removing memberships; use GRANT and REVOKE for that.)

Attributes not mentioned in the command retain their previous settings.

Database superusers can change any of these settings for any role. Roles having CREATEROLE privilege can change any of these settings except SUPERUSER, REPLICATION, and BYPASSRLS; but only for non-superuser and non-replication roles. Ordinary roles can only change their own password.

The second variant changes the name of the role.

Database superusers can rename any role. Roles having CREATEROLE privilege can rename non-superuser roles. The current session user cannot be renamed. (Connect as a different user if you need to do that.) Because MD5-encrypted passwords use the role name as cryptographic salt, renaming a role clears its password if the password is MD5-encrypted.

The remaining variants change a role’s session default for a configuration variable, either for all databases or, when the IN DATABASE clause is specified, only for sessions in the named database. If ALL is specified instead of a role name, this changes the setting for all roles. Using ALL with IN DATABASE is effectively the same as using the command ALTER DATABASE … SET ….

Whenever the role subsequently starts a new session, the specified value becomes the session default, overriding whatever setting is present in postgresql.conf or has been received from the postgres command line.

This only happens at login time; executing SET ROLE or SET SESSION AUTHORIZATION does not cause new configuration values to be set.

Settings set for all databases are overridden by database-specific settings attached to a role. Settings for specific databases or specific roles override settings for all roles.

Superusers can change anyone’s session defaults.

Roles having CREATEROLE privilege can change defaults for non-superuser roles. Ordinary roles can only set defaults for themselves. Certain configuration variables cannot be set this way, or can only be set if a superuser issues the command. Only superusers can change a setting for all roles in all databases.