set_role(7) [centos man page]
SET
ROLE(7) PostgreSQL 9.2.7 Documentation SET ROLE(7) NAME
SET_ROLE - set the current user identifier of the current session SYNOPSIS
SET [ SESSION | LOCAL ] ROLE role_name SET [ SESSION | LOCAL ] ROLE NONE RESET ROLE DESCRIPTION
This command sets the current user identifier of the current SQL session to be role_name. The role name can be written as either an identifier or a string literal. After SET ROLE, permissions checking for SQL commands is carried out as though the named role were the one that had logged in originally. The specified role_name must be a role that the current session user is a member of. (If the session user is a superuser, any role can be selected.) The SESSION and LOCAL modifiers act the same as for the regular SET(7) command. The NONE and RESET forms reset the current user identifier to be the current session user identifier. These forms can be executed by any user. NOTES
Using this command, it is possible to either add privileges or restrict one's privileges. If the session user role has the INHERITS attribute, then it automatically has all the privileges of every role that it could SET ROLE to; in this case SET ROLE effectively drops all the privileges assigned directly to the session user and to the other roles it is a member of, leaving only the privileges available to the named role. On the other hand, if the session user role has the NOINHERITS attribute, SET ROLE drops the privileges assigned directly to the session user and instead acquires the privileges available to the named role. In particular, when a superuser chooses to SET ROLE to a non-superuser role, she loses her superuser privileges. SET ROLE has effects comparable to SET SESSION AUTHORIZATION (SET_SESSION_AUTHORIZATION(7)), but the privilege checks involved are quite different. Also, SET SESSION AUTHORIZATION determines which roles are allowable for later SET ROLE commands, whereas changing roles with SET ROLE does not change the set of roles allowed to a later SET ROLE. SET ROLE does not process session variables as specified by the role's ALTER ROLE (ALTER_ROLE(7)) settings; this only happens during login. SET ROLE cannot be used within a SECURITY DEFINER function. EXAMPLES
SELECT SESSION_USER, CURRENT_USER; session_user | current_user --------------+-------------- peter | peter SET ROLE 'paul'; SELECT SESSION_USER, CURRENT_USER; session_user | current_user --------------+-------------- peter | paul COMPATIBILITY
PostgreSQL allows identifier syntax ("rolename"), while the SQL standard requires the role name to be written as a string literal. SQL does not allow this command during a transaction; PostgreSQL does not make this restriction because there is no reason to. The SESSION and LOCAL modifiers are a PostgreSQL extension, as is the RESET syntax. SEE ALSO
SET SESSION AUTHORIZATION (SET_SESSION_AUTHORIZATION(7)) PostgreSQL 9.2.7 2014-02-17 SET ROLE(7)
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ALTER
ROLE(7) SQL Commands ALTER ROLE(7) NAME
ALTER ROLE - change a database role SYNOPSIS
ALTER ROLE name [ [ WITH ] option [ ... ] ] 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' ALTER ROLE name RENAME TO newname ALTER ROLE name SET configuration_parameter { TO | = } { value | DEFAULT } ALTER ROLE name SET configuration_parameter FROM CURRENT ALTER ROLE name RESET configuration_parameter ALTER ROLE name RESET ALL DESCRIPTION
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 [cre- ate_role(7)]. (All the possible attributes are covered, except that there are no options for adding or removing memberships; use GRANT [grant(7)] and REVOKE [revoke(7)] 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, but only for non-supe- ruser 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 specified configuration variable. 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, so configuration settings associated with a role to which you've SET ROLE [set_role(7)] will be ignored. Superusers can change anyone's session defaults. Roles having CREATEROLE privilege can change defaults for non-superuser roles. Certain variables cannot be set this way, or can only be set if a superuser issues the command. PARAMETERS
name The name of the role whose attributes are to be altered. SUPERUSER NOSUPERUSER CREATEDB NOCREATEDB CREATEROLE NOCREATEROLE CREATEUSER NOCREATEUSER INHERIT NOINHERIT LOGIN NOLOGIN CONNECTION LIMIT connlimit PASSWORD password ENCRYPTED UNENCRYPTED VALID UNTIL 'timestamp' These clauses alter attributes originally set by CREATE ROLE [create_role(7)]. For more information, see the CREATE ROLE reference page. newname The new name of the role. configuration_parameter value Set this role's session default for the specified configuration parameter to the given value. If value is DEFAULT or, equivalently, RESET is used, the role-specific variable setting is removed, so the role will inherit the system-wide default setting in new ses- sions. Use RESET ALL to clear all role-specific settings. SET FROM CURRENT saves the session's current value of the parameter as the role-specific value. Role-specific variable setting take effect only at login; SET ROLE [set_role(7)] does not process role-specific variable settings. See SET [set(7)] and in the documentation for more information about allowed parameter names and values. NOTES
Use CREATE ROLE [create_role(7)] to add new roles, and DROP ROLE [drop_role(7)] to remove a role. ALTER ROLE cannot change a role's memberships. Use GRANT [grant(7)] and REVOKE [revoke(7)] to do that. 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. psql [psql(1)] contains a command password that can be used to safely change a role's password. It is also possible to tie a session default to a specific database rather than to a role; see ALTER DATABASE [alter_database(7)]. Role- specific settings override database-specific ones if there is a conflict. EXAMPLES
Change a role's password: ALTER ROLE davide WITH PASSWORD 'hu8jmn3'; Remove a role's password: ALTER ROLE davide WITH PASSWORD NULL; Change a password expiration date, specifying that the password should expire at midday on 4th May 2015 using the time zone which is one hour ahead of UTC: ALTER ROLE chris VALID UNTIL 'May 4 12:00:00 2015 +1'; Make a password valid forever: ALTER ROLE fred VALID UNTIL 'infinity'; Give a role the ability to create other roles and new databases: ALTER ROLE miriam CREATEROLE CREATEDB; Give a role a non-default setting of the maintenance_work_mem parameter: ALTER ROLE worker_bee SET maintenance_work_mem = 100000; COMPATIBILITY
The ALTER ROLE statement is a PostgreSQL extension. SEE ALSO
CREATE ROLE [create_role(7)], DROP ROLE [drop_role(7)], SET [set(7)] SQL - Language Statements 2010-05-14 ALTER ROLE(7)