На странице документации GRANT не отображается запись для UNKNOWN
:
GRANT { { SELECT | INSERT | UPDATE | DELETE | REFERENCES } [,...] | ALL [ PRIVILEGES ] }
ON { [ TABLE ] table_name [, ...] | ALL TABLES IN SCHEMA schema_name [, ...] }
TO { username [ WITH GRANT OPTION ] | GROUP group_name | PUBLIC } [, ...]
GRANT { { CREATE | TEMPORARY | TEMP } [,...] | ALL [ PRIVILEGES ] }
ON DATABASE db_name [, ...]
TO { username [ WITH GRANT OPTION ] | GROUP group_name | PUBLIC } [, ...]
GRANT { { CREATE | USAGE } [,...] | ALL [ PRIVILEGES ] }
ON SCHEMA schema_name [, ...]
TO { username [ WITH GRANT OPTION ] | GROUP group_name | PUBLIC } [, ...]
GRANT { EXECUTE | ALL [ PRIVILEGES ] }
ON { FUNCTION function_name ( [ [ argname ] argtype [, ...] ] ) [, ...] | ALL FUNCTIONS IN SCHEMA schema_name [, ...] }
TO { username [ WITH GRANT OPTION ] | GROUP group_name | PUBLIC } [, ...]
GRANT { EXECUTE | ALL [ PRIVILEGES ] }
ON { PROCEDURE procedure_name ( [ [ argname ] argtype [, ...] ] ) [, ...] | ALL PROCEDURES IN SCHEMA schema_name [, ...] }
TO { username [ WITH GRANT OPTION ] | GROUP group_name | PUBLIC } [, ...]
GRANT USAGE
ON LANGUAGE language_name [, ...]
TO { username [ WITH GRANT OPTION ] | GROUP group_name | PUBLIC } [, ...]