from parent
   views.  In <code class="command">UPDATE</code>,
   expressions to assign to target columns must use only built-in data types,
   <code class="literal">IMMUTABLE</code> operators, or <code class="literal">IMMUTABLE</code> functions,
   to reduce the risk of misexecution of the query.
  </p><p>
   When <code class="filename">postgres_fdw</code> encounters a join between foreign tables on
   the same foreign server, it sends the entire join to the foreign server,
   unless for some reason it bel