Passing data from database in href

Passing Data to Href.php

<?php
  $con = new mysqli("localhost", "root", "", "test");
  $sql = "select * from userdata"; //userdata is a table
  $stmt = $con->query($sql);
  if($stmt){
	if($stmt->num_rows>0){
          $row = $stmt->fetch_assoc();?>
            <a href="something.php?userid=<?php echo $row['userid']; ?>">Go To Something Page</a>
        <?php }
      }
//follow this process in same way

?>