on of the functions to true if you don't use the returned iterator to write, which also promotes concurrency and overall performance. </p>
      </div>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idp50505600"></a>Class</h3>
            </div>
          </div>
        </div>
        <p>
  <a class="link" href="db_map.html" title="Chapter 5.  Db_map">db_map</a>
     </p>
      </div>
    </div>
   