Allow CURRENT/SESSION_USER to be used in certain commands

Commands such as ALTER USER, ALTER GROUP, ALTER ROLE, GRANT, and the
various ALTER OBJECT / OWNER TO, as well as ad-hoc clauses related to
roles such as the AUTHORIZATION clause of CREATE SCHEMA, the FOR clause
of CREATE USER MAPPING, and the FOR ROLE clause of ALTER DEFAULT
PRIVILEGES can now take the keywords CURRENT_USER and SESSION_USER as
user specifiers in place of an explicit user name.

This commit also fixes some quite ugly handling of special standards-
mandated syntax in CREATE USER MAPPING, which in particular would fail
to work in presence of a role named "current_user".

The special role specifiers PUBLIC and NONE also have more consistent
handling now.

Also take the opportunity to add location tracking to user specifiers.

Authors: Kyotaro Horiguchi.  Heavily reworked by Álvaro Herrera.
Reviewed by: Rushabh Lathia, Adam Brightwell, Marti Raudsepp.

doc/src/sgml/ref/alter_aggregate.sgml

@@ -22,7 +22,8 @@ PostgreSQL documentation
  <refsynopsisdiv>
 <synopsis>
 ALTER AGGREGATE <replaceable>name</replaceable> ( <replaceable>aggregate_signature</replaceable> ) RENAME TO <replaceable>new_name</replaceable>
-ALTER AGGREGATE <replaceable>name</replaceable> ( <replaceable>aggregate_signature</replaceable> ) OWNER TO <replaceable>new_owner</replaceable>
+ALTER AGGREGATE <replaceable>name</replaceable> ( <replaceable>aggregate_signature</replaceable> )
+                OWNER TO { <replaceable>new_owner</replaceable> | CURRENT_USER | SESSION_USER }
 ALTER AGGREGATE <replaceable>name</replaceable> ( <replaceable>aggregate_signature</replaceable> ) SET SCHEMA <replaceable>new_schema</replaceable>
 
 <phrase>where <replaceable>aggregate_signature</replaceable> is:</phrase>

doc/src/sgml/ref/alter_collation.sgml

@@ -22,7 +22,7 @@ PostgreSQL documentation
  <refsynopsisdiv>
 <synopsis>
 ALTER COLLATION <replaceable>name</replaceable> RENAME TO <replaceable>new_name</replaceable>
-ALTER COLLATION <replaceable>name</replaceable> OWNER TO <replaceable>new_owner</replaceable>
+ALTER COLLATION <replaceable>name</replaceable> OWNER TO { <replaceable>new_owner</replaceable> | CURRENT_USER | SESSION_USER }
 ALTER COLLATION <replaceable>name</replaceable> SET SCHEMA <replaceable>new_schema</replaceable>
 </synopsis>
  </refsynopsisdiv>

doc/src/sgml/ref/alter_conversion.sgml

@@ -22,7 +22,7 @@ PostgreSQL documentation
  <refsynopsisdiv>
 <synopsis>
 ALTER CONVERSION <replaceable>name</replaceable> RENAME TO <replaceable>new_name</replaceable>
-ALTER CONVERSION <replaceable>name</replaceable> OWNER TO <replaceable>new_owner</replaceable>
+ALTER CONVERSION <replaceable>name</replaceable> OWNER TO { <replaceable>new_owner</replaceable> | CURRENT_USER | SESSION_USER }
 ALTER CONVERSION <replaceable>name</replaceable> SET SCHEMA <replaceable>new_schema</replaceable>
 </synopsis>
  </refsynopsisdiv>

doc/src/sgml/ref/alter_database.sgml

@@ -31,7 +31,7 @@ ALTER DATABASE <replaceable class="PARAMETER">name</replaceable> [ [ WITH ] <rep
 
 ALTER DATABASE <replaceable class="PARAMETER">name</replaceable> RENAME TO <replaceable>new_name</replaceable>
 
-ALTER DATABASE <replaceable class="PARAMETER">name</replaceable> OWNER TO <replaceable>new_owner</replaceable>
+ALTER DATABASE <replaceable class="PARAMETER">name</replaceable> OWNER TO { <replaceable>new_owner</replaceable> | CURRENT_USER | SESSION_USER }
 
 ALTER DATABASE <replaceable class="PARAMETER">name</replaceable> SET TABLESPACE <replaceable class="PARAMETER">new_tablespace</replaceable>
 

doc/src/sgml/ref/alter_domain.sgml

@@ -36,7 +36,7 @@ ALTER DOMAIN <replaceable class="PARAMETER">name</replaceable>
 ALTER DOMAIN <replaceable class="PARAMETER">name</replaceable>
     VALIDATE CONSTRAINT <replaceable class="PARAMETER">constraint_name</replaceable>
 ALTER DOMAIN <replaceable class="PARAMETER">name</replaceable>
-    OWNER TO <replaceable class="PARAMETER">new_owner</replaceable>
+    OWNER TO { <replaceable class="PARAMETER">new_owner</replaceable> | CURRENT_USER | SESSION_USER }
 ALTER DOMAIN <replaceable class="PARAMETER">name</replaceable>
     RENAME TO <replaceable class="PARAMETER">new_name</replaceable>
 ALTER DOMAIN <replaceable class="PARAMETER">name</replaceable>

doc/src/sgml/ref/alter_event_trigger.sgml

@@ -23,7 +23,7 @@ PostgreSQL documentation
 <synopsis>
 ALTER EVENT TRIGGER <replaceable class="PARAMETER">name</replaceable> DISABLE
 ALTER EVENT TRIGGER <replaceable class="PARAMETER">name</replaceable> ENABLE [ REPLICA | ALWAYS ]
-ALTER EVENT TRIGGER <replaceable class="PARAMETER">name</replaceable> OWNER TO <replaceable class="PARAMETER">new_owner</replaceable>
+ALTER EVENT TRIGGER <replaceable class="PARAMETER">name</replaceable> OWNER TO { <replaceable class="PARAMETER">new_owner</replaceable> | CURRENT_USER | SESSION_USER }
 ALTER EVENT TRIGGER <replaceable class="PARAMETER">name</replaceable> RENAME TO <replaceable class="PARAMETER">new_name</replaceable>
 </synopsis>
  </refsynopsisdiv>

doc/src/sgml/ref/alter_foreign_data_wrapper.sgml

@@ -25,7 +25,7 @@ ALTER FOREIGN DATA WRAPPER <replaceable class="parameter">name</replaceable>
     [ HANDLER <replaceable class="parameter">handler_function</replaceable> | NO HANDLER ]
     [ VALIDATOR <replaceable class="parameter">validator_function</replaceable> | NO VALIDATOR ]
     [ OPTIONS ( [ ADD | SET | DROP ] <replaceable class="PARAMETER">option</replaceable> ['<replaceable class="PARAMETER">value</replaceable>'] [, ... ]) ]
-ALTER FOREIGN DATA WRAPPER <replaceable class="parameter">name</replaceable> OWNER TO <replaceable>new_owner</replaceable>
+ALTER FOREIGN DATA WRAPPER <replaceable class="parameter">name</replaceable> OWNER TO { <replaceable>new_owner</replaceable> | CURRENT_USER | SESSION_USER }
 ALTER FOREIGN DATA WRAPPER <replaceable class="parameter">name</replaceable> RENAME TO <replaceable>new_name</replaceable>
 </synopsis>
  </refsynopsisdiv>

doc/src/sgml/ref/alter_foreign_table.sgml

@@ -48,7 +48,7 @@ ALTER FOREIGN TABLE [ IF EXISTS ] <replaceable class="PARAMETER">name</replaceab
     ENABLE TRIGGER [ <replaceable class="PARAMETER">trigger_name</replaceable> | ALL | USER ]
     ENABLE REPLICA TRIGGER <replaceable class="PARAMETER">trigger_name</replaceable>
     ENABLE ALWAYS TRIGGER <replaceable class="PARAMETER">trigger_name</replaceable>
-    OWNER TO <replaceable class="PARAMETER">new_owner</replaceable>
+    OWNER TO { <replaceable class="PARAMETER">new_owner</replaceable> | CURRENT_USER | SESSION_USER }
     OPTIONS ( [ ADD | SET | DROP ] <replaceable class="PARAMETER">option</replaceable> ['<replaceable class="PARAMETER">value</replaceable>'] [, ... ])
 </synopsis>
  </refsynopsisdiv>

doc/src/sgml/ref/alter_function.sgml

@@ -26,7 +26,7 @@ ALTER FUNCTION <replaceable>name</replaceable> ( [ [ <replaceable class="paramet
 ALTER FUNCTION <replaceable>name</replaceable> ( [ [ <replaceable class="parameter">argmode</replaceable> ] [ <replaceable class="parameter">argname</replaceable> ] <replaceable class="parameter">argtype</replaceable> [, ...] ] )
     RENAME TO <replaceable>new_name</replaceable>
 ALTER FUNCTION <replaceable>name</replaceable> ( [ [ <replaceable class="parameter">argmode</replaceable> ] [ <replaceable class="parameter">argname</replaceable> ] <replaceable class="parameter">argtype</replaceable> [, ...] ] )
-    OWNER TO <replaceable>new_owner</replaceable>
+    OWNER TO { <replaceable>new_owner</replaceable> | CURRENT_USER | SESSION_USER }
 ALTER FUNCTION <replaceable>name</replaceable> ( [ [ <replaceable class="parameter">argmode</replaceable> ] [ <replaceable class="parameter">argname</replaceable> ] <replaceable class="parameter">argtype</replaceable> [, ...] ] )
     SET SCHEMA <replaceable>new_schema</replaceable>
 

doc/src/sgml/ref/alter_group.sgml

@@ -21,8 +21,14 @@ PostgreSQL documentation
 
  <refsynopsisdiv>
 <synopsis>
-ALTER GROUP <replaceable class="PARAMETER">group_name</replaceable> ADD USER <replaceable class="PARAMETER">user_name</replaceable> [, ... ]
-ALTER GROUP <replaceable class="PARAMETER">group_name</replaceable> DROP USER <replaceable class="PARAMETER">user_name</replaceable> [, ... ]
+ALTER GROUP <replaceable class="PARAMETER">role_specification</replaceable> ADD USER <replaceable class="PARAMETER">user_name</replaceable> [, ... ]
+ALTER GROUP <replaceable class="PARAMETER">role_specification</replaceable> DROP USER <replaceable class="PARAMETER">user_name</replaceable> [, ... ]
+
+<phrase>where <replaceable class="PARAMETER">role_specification</replaceable> can be:</phrase>
+
+    <replaceable class="PARAMETER">role_name</replaceable>
+  | CURRENT_USER
+  | SESSION_USER
 
 ALTER GROUP <replaceable class="PARAMETER">group_name</replaceable> RENAME TO <replaceable>new_name</replaceable>
 </synopsis>

doc/src/sgml/ref/alter_language.sgml

@@ -22,7 +22,7 @@ PostgreSQL documentation
  <refsynopsisdiv>
 <synopsis>
 ALTER [ PROCEDURAL ] LANGUAGE <replaceable>name</replaceable> RENAME TO <replaceable>new_name</replaceable>
-ALTER [ PROCEDURAL ] LANGUAGE <replaceable>name</replaceable> OWNER TO <replaceable>new_owner</replaceable>
+ALTER [ PROCEDURAL ] LANGUAGE <replaceable>name</replaceable> OWNER TO { <replaceable>new_owner</replaceable> | CURRENT_USER | SESSION_USER }
 </synopsis>
  </refsynopsisdiv>
 

doc/src/sgml/ref/alter_large_object.sgml

@@ -21,7 +21,7 @@ PostgreSQL documentation
 
  <refsynopsisdiv>
 <synopsis>
-ALTER LARGE OBJECT <replaceable class="PARAMETER">large_object_oid</replaceable> OWNER TO <replaceable>new_owner</replaceable>
+ALTER LARGE OBJECT <replaceable class="PARAMETER">large_object_oid</replaceable> { OWNER TO <replaceable>new_owner</replaceable> | CURRENT_USER | SESSION_USER }
 </synopsis>
  </refsynopsisdiv>
 

doc/src/sgml/ref/alter_materialized_view.sgml

@@ -42,7 +42,7 @@ ALTER MATERIALIZED VIEW ALL IN TABLESPACE <replaceable class="parameter">name</r
     SET WITHOUT CLUSTER
     SET ( <replaceable class="PARAMETER">storage_parameter</replaceable> = <replaceable class="PARAMETER">value</replaceable> [, ... ] )
     RESET ( <replaceable class="PARAMETER">storage_parameter</replaceable> [, ... ] )
-    OWNER TO <replaceable class="PARAMETER">new_owner</replaceable>
+    OWNER TO { <replaceable class="PARAMETER">new_owner</replaceable> | CURRENT_USER | SESSION_USER }
     SET TABLESPACE <replaceable class="PARAMETER">new_tablespace</replaceable>
 </synopsis>
  </refsynopsisdiv>

doc/src/sgml/ref/alter_opclass.sgml

@@ -21,9 +21,14 @@ PostgreSQL documentation
 
  <refsynopsisdiv>
 <synopsis>
-ALTER OPERATOR CLASS <replaceable>name</replaceable> USING <replaceable class="parameter">index_method</replaceable> RENAME TO <replaceable>new_name</replaceable>
-ALTER OPERATOR CLASS <replaceable>name</replaceable> USING <replaceable class="parameter">index_method</replaceable> OWNER TO <replaceable>new_owner</replaceable>
-ALTER OPERATOR CLASS <replaceable>name</replaceable> USING <replaceable class="parameter">index_method</replaceable> SET SCHEMA <replaceable>new_schema</replaceable>
+ALTER OPERATOR CLASS <replaceable>name</replaceable> USING <replaceable class="parameter">index_method</replaceable>
+           RENAME TO <replaceable>new_name</replaceable>
+
+ALTER OPERATOR CLASS <replaceable>name</replaceable> USING <replaceable class="parameter">index_method</replaceable>
+          { OWNER TO <replaceable>new_owner</replaceable> | CURRENT_USER | SESSION_USER }
+
+ALTER OPERATOR CLASS <replaceable>name</replaceable> USING <replaceable class="parameter">index_method</replaceable>
+          SET SCHEMA <replaceable>new_schema</replaceable>
 </synopsis>
  </refsynopsisdiv>
 

doc/src/sgml/ref/alter_operator.sgml

@@ -21,8 +21,11 @@ PostgreSQL documentation
 
  <refsynopsisdiv>
 <synopsis>
-ALTER OPERATOR <replaceable>name</replaceable> ( { <replaceable>left_type</replaceable> | NONE } , { <replaceable>right_type</replaceable> | NONE } ) OWNER TO <replaceable>new_owner</replaceable>
-ALTER OPERATOR <replaceable>name</replaceable> ( { <replaceable>left_type</replaceable> | NONE } , { <replaceable>right_type</replaceable> | NONE } ) SET SCHEMA <replaceable>new_schema</replaceable>
+ALTER OPERATOR <replaceable>name</replaceable> ( { <replaceable>left_type</replaceable> | NONE } , { <replaceable>right_type</replaceable> | NONE } )
+             { OWNER TO <replaceable>new_owner</replaceable> | CURRENT_USER | SESSION_USER }
+
+ALTER OPERATOR <replaceable>name</replaceable> ( { <replaceable>left_type</replaceable> | NONE } , { <replaceable>right_type</replaceable> | NONE } )
+               SET SCHEMA <replaceable>new_schema</replaceable>
 </synopsis>
  </refsynopsisdiv>
 

doc/src/sgml/ref/alter_opfamily.sgml

@@ -22,16 +22,25 @@ PostgreSQL documentation
  <refsynopsisdiv>
 <synopsis>
 ALTER OPERATOR FAMILY <replaceable>name</replaceable> USING <replaceable class="parameter">index_method</replaceable> ADD
-  {  OPERATOR <replaceable class="parameter">strategy_number</replaceable> <replaceable class="parameter">operator_name</replaceable> ( <replaceable class="parameter">op_type</replaceable>, <replaceable class="parameter">op_type</replaceable> ) [ FOR SEARCH | FOR ORDER BY <replaceable class="parameter">sort_family_name</replaceable> ]
-   | FUNCTION <replaceable class="parameter">support_number</replaceable> [ ( <replaceable class="parameter">op_type</replaceable> [ , <replaceable class="parameter">op_type</replaceable> ] ) ] <replaceable class="parameter">function_name</replaceable> ( <replaceable class="parameter">argument_type</replaceable> [, ...] )
+  {  OPERATOR <replaceable class="parameter">strategy_number</replaceable> <replaceable class="parameter">operator_name</replaceable> ( <replaceable class="parameter">op_type</replaceable>, <replaceable class="parameter">op_type</replaceable> )
+              [ FOR SEARCH | FOR ORDER BY <replaceable class="parameter">sort_family_name</replaceable> ]
+   | FUNCTION <replaceable class="parameter">support_number</replaceable> [ ( <replaceable class="parameter">op_type</replaceable> [ , <replaceable class="parameter">op_type</replaceable> ] ) ]
+              <replaceable class="parameter">function_name</replaceable> ( <replaceable class="parameter">argument_type</replaceable> [, ...] )
   } [, ... ]
+
 ALTER OPERATOR FAMILY <replaceable>name</replaceable> USING <replaceable class="parameter">index_method</replaceable> DROP
   {  OPERATOR <replaceable class="parameter">strategy_number</replaceable> ( <replaceable class="parameter">op_type</replaceable> [ , <replaceable class="parameter">op_type</replaceable> ] )
    | FUNCTION <replaceable class="parameter">support_number</replaceable> ( <replaceable class="parameter">op_type</replaceable> [ , <replaceable class="parameter">op_type</replaceable> ] )
   } [, ... ]
-ALTER OPERATOR FAMILY <replaceable>name</replaceable> USING <replaceable class="parameter">index_method</replaceable> RENAME TO <replaceable>new_name</replaceable>
-ALTER OPERATOR FAMILY <replaceable>name</replaceable> USING <replaceable class="parameter">index_method</replaceable> OWNER TO <replaceable>new_owner</replaceable>
-ALTER OPERATOR FAMILY <replaceable>name</replaceable> USING <replaceable class="parameter">index_method</replaceable> SET SCHEMA <replaceable>new_schema</replaceable>
+
+ALTER OPERATOR FAMILY <replaceable>name</replaceable> USING <replaceable class="parameter">index_method</replaceable>
+            RENAME TO <replaceable>new_name</replaceable>
+
+ALTER OPERATOR FAMILY <replaceable>name</replaceable> USING <replaceable class="parameter">index_method</replaceable>
+             OWNER TO { <replaceable>new_owner</replaceable> | CURRENT_USER | SESSION_USER }
+
+ALTER OPERATOR FAMILY <replaceable>name</replaceable> USING <replaceable class="parameter">index_method</replaceable>
+           SET SCHEMA <replaceable>new_schema</replaceable>
 </synopsis>
  </refsynopsisdiv>
 

doc/src/sgml/ref/alter_role.sgml

@@ -21,7 +21,7 @@ PostgreSQL documentation
 
  <refsynopsisdiv>
 <synopsis>
-ALTER ROLE <replaceable class="PARAMETER">name</replaceable> [ [ WITH ] <replaceable class="PARAMETER">option</replaceable> [ ... ] ]
+ALTER ROLE <replaceable class="PARAMETER">role_specification</replaceable> [ WITH ] <replaceable class="PARAMETER">option</replaceable> [ ... ]
 
 <phrase>where <replaceable class="PARAMETER">option</replaceable> can be:</phrase>
 
@@ -39,10 +39,16 @@ ALTER ROLE <replaceable class="PARAMETER">name</replaceable> [ [ WITH ] <replace
 
 ALTER ROLE <replaceable class="PARAMETER">name</replaceable> RENAME TO <replaceable>new_name</replaceable>
 
-ALTER ROLE <replaceable class="PARAMETER">name</replaceable> [ IN DATABASE <replaceable class="PARAMETER">database_name</replaceable> ] SET <replaceable>configuration_parameter</replaceable> { TO | = } { <replaceable>value</replaceable> | DEFAULT }
-ALTER ROLE { <replaceable class="PARAMETER">name</replaceable> | ALL } [ IN DATABASE <replaceable class="PARAMETER">database_name</replaceable> ] SET <replaceable>configuration_parameter</replaceable> FROM CURRENT
-ALTER ROLE { <replaceable class="PARAMETER">name</replaceable> | ALL } [ IN DATABASE <replaceable class="PARAMETER">database_name</replaceable> ] RESET <replaceable>configuration_parameter</replaceable>
-ALTER ROLE { <replaceable class="PARAMETER">name</replaceable> | ALL } [ IN DATABASE <replaceable class="PARAMETER">database_name</replaceable> ] RESET ALL
+ALTER ROLE { <replaceable class="PARAMETER">role_specification</replaceable> | ALL } [ IN DATABASE <replaceable class="PARAMETER">database_name</replaceable> ] SET <replaceable>configuration_parameter</replaceable> { TO | = } { <replaceable>value</replaceable> | DEFAULT }
+ALTER ROLE { <replaceable class="PARAMETER">role_specification</replaceable> | ALL } [ IN DATABASE <replaceable class="PARAMETER">database_name</replaceable> ] SET <replaceable>configuration_parameter</replaceable> FROM CURRENT
+ALTER ROLE { <replaceable class="PARAMETER">role_specification</replaceable> | ALL } [ IN DATABASE <replaceable class="PARAMETER">database_name</replaceable> ] RESET <replaceable>configuration_parameter</replaceable>
+ALTER ROLE { <replaceable class="PARAMETER">role_specification</replaceable> | ALL } [ IN DATABASE <replaceable class="PARAMETER">database_name</replaceable> ] RESET ALL
+
+<phrase>where <replaceable class="PARAMETER">role_specification</replaceable> can be:</phrase>
+
+    [ GROUP ] <replaceable class="PARAMETER">role_name</replaceable>
+  | CURRENT_USER
+  | SESSION_USER
 </synopsis>
  </refsynopsisdiv>
 
@@ -128,6 +134,25 @@ ALTER ROLE { <replaceable class="PARAMETER">name</replaceable> | ALL } [ IN DATA
       </listitem>
      </varlistentry>
 
+     <varlistentry>
+      <term>CURRENT_USER</term>
+      <listitem>
+       <para>
+        Alter the current user instead of an explicitely identified role.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term>SESSION_USER</term>
+      <listitem>
+       <para>
+        Alter the current session user instead of an explicitely identified
+        role.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry>
       <term><literal>SUPERUSER</literal></term>
       <term><literal>NOSUPERUSER</literal></term>

doc/src/sgml/ref/alter_schema.sgml

@@ -22,7 +22,7 @@ PostgreSQL documentation
  <refsynopsisdiv>
 <synopsis>
 ALTER SCHEMA <replaceable>name</replaceable> RENAME TO <replaceable>new_name</replaceable>
-ALTER SCHEMA <replaceable>name</replaceable> OWNER TO <replaceable>new_owner</replaceable>
+ALTER SCHEMA <replaceable>name</replaceable> OWNER TO { <replaceable>new_owner</replaceable> | CURRENT_USER | SESSION_USER }
 </synopsis>
  </refsynopsisdiv>
 

doc/src/sgml/ref/alter_sequence.sgml

@@ -29,7 +29,7 @@ ALTER SEQUENCE [ IF EXISTS ] <replaceable class="parameter">name</replaceable> [
     [ RESTART [ [ WITH ] <replaceable class="parameter">restart</replaceable> ] ]
     [ CACHE <replaceable class="parameter">cache</replaceable> ] [ [ NO ] CYCLE ]
     [ OWNED BY { <replaceable class="parameter">table_name</replaceable>.<replaceable class="parameter">column_name</replaceable> | NONE } ]
-ALTER SEQUENCE [ IF EXISTS ] <replaceable class="parameter">name</replaceable> OWNER TO <replaceable class="PARAMETER">new_owner</replaceable>
+ALTER SEQUENCE [ IF EXISTS ] <replaceable class="parameter">name</replaceable> OWNER TO { <replaceable class="PARAMETER">new_owner</replaceable> | CURRENT_USER | SESSION_USER }
 ALTER SEQUENCE [ IF EXISTS ] <replaceable class="parameter">name</replaceable> RENAME TO <replaceable class="parameter">new_name</replaceable>
 ALTER SEQUENCE [ IF EXISTS ] <replaceable class="parameter">name</replaceable> SET SCHEMA <replaceable class="parameter">new_schema</replaceable>
 </synopsis>

doc/src/sgml/ref/alter_server.sgml

@@ -23,7 +23,7 @@ PostgreSQL documentation
 <synopsis>
 ALTER SERVER <replaceable class="parameter">name</replaceable> [ VERSION '<replaceable class="parameter">new_version</replaceable>' ]
     [ OPTIONS ( [ ADD | SET | DROP ] <replaceable class="PARAMETER">option</replaceable> ['<replaceable class="PARAMETER">value</replaceable>'] [, ... ] ) ]
-ALTER SERVER <replaceable class="PARAMETER">name</replaceable> OWNER TO <replaceable>new_owner</replaceable>
+ALTER SERVER <replaceable class="PARAMETER">name</replaceable> OWNER TO { <replaceable>new_owner</replaceable> | CURRENT_USER | SESSION_USER }
 ALTER SERVER <replaceable class="PARAMETER">name</replaceable> RENAME TO <replaceable>new_name</replaceable>
 </synopsis>
  </refsynopsisdiv>