  function that was added since the remote server's release might be sent
   to it for execution, resulting in <span class="quote">“<span class="quote">function does not exist</span>”</span> or
   a similar error.  This type of failure can be worked around by
   rewriting the query, for example by embedding the foreign table
   reference in a sub-<code class="literal">SELECT</code> with <code class="literal">OFFSET 0</code> as an
   optimization fence, and placing the problematic function or operator
  