s the first unique key.</span></p>
              <p><span class="ts3">&nbsp;</span></p>
            </td>
          </tr>
          <tr class="row0">
            <td class="cell23">
              <p class="ps13"><a id="STRUCTURE_KEYS"></a><span class="ts14">&lt;STRUCTURE_KEYS&gt;</span></p>
            </td>
            <td class="cell24">
              <p class="ps2"><span class="ts3">Inserts the total number of keys defined in the structure.</span></p>
              <p class="ps2"><span class="t