tever it costs to be done on the remote
    server, plus some overhead for communication.  The most reliable way to
    get such an estimate is to ask the remote server and then add something
    for overhead — but for simple queries, it may not be worth the cost
    of an additional remote query to get a cost estimate.
    So <code class="filename">postgres_fdw</code> provides the following options to control
    how cost estimation is done:
   </p><div class="variablelist"><dl class="variablelist"><dt><