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SET SESSION AUTHORIZATION(7) PostgreSQL 12.3 Documentation SET SESSION AUTHORIZATION(7)
NAME
SET_SESSION_AUTHORIZATION - set the session user identifier and the current user
identifier of the current session
SYNOPSIS
SET [ SESSION | LOCAL ] SESSION AUTHORIZATION user_name
SET [ SESSION | LOCAL ] SESSION AUTHORIZATION DEFAULT
RESET SESSION AUTHORIZATION
DESCRIPTION
This command sets the session user identifier and the current user identifier of the
current SQL session to be user_name. The user name can be written as either an identifier
or a string literal. Using this command, it is possible, for example, to temporarily
become an unprivileged user and later switch back to being a superuser.
The session user identifier is initially set to be the (possibly authenticated) user name
provided by the client. The current user identifier is normally equal to the session user
identifier, but might change temporarily in the context of SECURITY DEFINER functions and
similar mechanisms; it can also be changed by SET ROLE (SET_ROLE(7)). The current user
identifier is relevant for permission checking.
The session user identifier can be changed only if the initial session user (the
authenticated user) had the superuser privilege. Otherwise, the command is accepted only
if it specifies the authenticated user name.
The SESSION and LOCAL modifiers act the same as for the regular SET(7) command.
The DEFAULT and RESET forms reset the session and current user identifiers to be the
originally authenticated user name. These forms can be executed by any user.
NOTES
SET SESSION AUTHORIZATION cannot be used within a SECURITY DEFINER function.
EXAMPLES
SELECT SESSION_USER, CURRENT_USER;
session_user | current_user
--------------+--------------
peter | peter
SET SESSION AUTHORIZATION 'paul';
SELECT SESSION_USER, CURRENT_USER;
session_user | current_user
--------------+--------------
paul | paul
COMPATIBILITY
The SQL standard allows some other expressions to appear in place of the literal
user_name, but these options are not important in practice. PostgreSQL allows identifier
syntax ("username"), which SQL does not. 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.
The privileges necessary to execute this command are left implementation-defined by the
standard.
SEE ALSO
SET ROLE (SET_ROLE(7))
PostgreSQL 12.3 2020 SET SESSION AUTHORIZATION(7)
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