a <code class="command">GRANT</code> or <code class="command">REVOKE</code>
    command, the command is performed as though it were issued by the
    owner of the affected object.  (Since roles do not have owners, in the
    case of a <code class="command">GRANT</code> of role membership, the command is
    performed as though it were issued by the bootstrap superuser.)
    Since all privileges ultimately come
    from the object owner (possibly indirectly via chains of grant options),
    it is possible fo