title: php dropdown selected value
body: <p>I'm having an edit form and within a dropdown box with movie-titles.
  One of them should be selected though, so say DVD_id: 100.
  How do I make this work in the code below?</p>
  
  <pre><code>        &lt;div class="form-group"&gt;
          &lt;label for="Site name" class="col-md-4 control-label"&gt;DVD Title&lt;/label&gt;
          &lt;?php
          $query = "Select DISTINCT dvd.dvdname, dvd.dvd_id, FROM DVD where ORDER BY dvd.dvdname";
          $result = mysql_query($query) or die ("Couldn�t execute query.");?&gt;
          &lt;div class="col-md-8"&gt;
              &lt;select id="box" name="dvdtitlefield" class="selectpicker form-control" multiple title="Choose one of the following..." &gt;
                  &lt;?php
                  while ($row = mysql_fetch_assoc($result))
                  {
                      extract($row);
                      echo '&lt;option value="'. $dvd_id .'"&gt;'. $dvdname .'&lt;/option&gt;';
                  }?&gt;
              &lt;/select&gt;
          &lt;/div&gt;
      &lt;/div&gt;
  </code></pre>