not supported anymore.
     </p></dd><dt><span class="term"><code class="literal">ON COMMIT</code></span></dt><dd><p>
      The behavior of temporary tables at the end of a transaction
      block can be controlled using <code class="literal">ON COMMIT</code>.
      The three options are:

      </p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="literal">PRESERVE ROWS</code></span></dt><dd><p>
          No special action is taken at the ends of transactions.
         