Postgres 允许 UPDATE 但只授予 SELECT

表的所​​有者x是 user dave。

只有SELECT被授予cloudsqlsuperuser，但用户anton能够更新表中的数据x。怎么可能？

=> \du
                                                         List of roles
         Role name         |                         Attributes                         |               Member of               
---------------------------+------------------------------------------------------------+---------------------------------------
 anton                     | Create role, Create DB                                     | {cloudsqlsuperuser}
 cloudsqladmin             | Superuser, Create role, Create DB, Replication, Bypass RLS | {}
 cloudsqlagent             | Create role, Create DB                                     | {cloudsqlsuperuser}
 cloudsqliamserviceaccount | Cannot login                                               | {}
 cloudsqliamuser           | Cannot login                                               | {}
 cloudsqlimportexport      | Create role, Create DB                                     | {cloudsqlsuperuser}
 cloudsqlreplica           | Replication                                                | {pg_monitor}
 cloudsqlsuperuser         | Create role, Create DB                                     | {pg_monitor,pg_signal_backend}
 dave                      | Create role, Create DB                                     | {cloudsqlsuperuser,postgres}

=> \dt
                   List of relations
 Schema |           Name           | Type  |   Owner   
--------+--------------------------+-------+-----------
 public | x                        | table | dave

=> \z x
                                      Access privileges
 Schema |     Name     | Type  |       Access privileges       | Column privileges | Policies 
--------+--------------+-------+-------------------------------+-------------------+----------
 public | x            | table | dave=arwdDxt/dave            +|                   | 
        |              |       | =arwdDxt/dave                +|                   | 
        |              |       | cloudsqlsuperuser=r/dave     +|                   | 
(1 row)

我能够以anton用户身份进行更新。不应该禁止吗？

=> update x set ...
UPDATE 1