</code> or <code class="literal">REPEATABLE READ</code>
   isolation level, but it might be surprising for a <code class="literal">READ
   COMMITTED</code> local transaction.  A future
   <span class="productname">PostgreSQL</span> release might modify these rules.
  </p><p>
   Note that it is currently not supported by
   <code class="filename">postgres_fdw</code> to prepare the remote transaction for
   two-phase commit.
  </p></div><div class="sect2" id="POSTGRES-FDW-REMOTE-QUERY-OPTIMIZATION"><div class