Use PDO fetch method to display table rows

pdo_fetch_assoc.php

<?php
  $sql = 'SELECT * FROM people';
  $result = $db->query($sql);
  $numrows = $result->rowCount();
  ?>
<table>
  <tr>
    <th>First name</th>
    <th>Last name</th>
    <th>Gender</th>
  </tr>
  <?php if ($numrows > 0) {
    echo "<p>We have found $numrows results:</p>";
    while($row = $result -> fetch(PDO::FETCH_ASSOC)) { ?>
  <tr>
    <td><?php echo $row['first_name']; ?></td>
    <td><?php echo $row['last_name']; ?></td>
    <td><?php echo $row['gender']; ?></td>
  </tr>
  <?php	} 
    } else {
    	echo "<p>There are no results to display</p>";
    }?>
</table>