MYSQLI SELECT FROM

how do i show my database to users by using the same php script? Over here, after i get the $_POST data from my form, i want to show the whole table to the user. How can i achieve that? Thank You GURUS in advance! (:

<?php
$db_hostname = 'localhost';
$db_database = 'userdata';
$db_username = '';
$db_password = '';

$mysqli = new mysqli($db_hostname, $db_username, $db_password, $db_database);

if (mysqli_connect_errno())
  {
  echo "Failed to connect to MySQL: " . mysqli_connect_error();
  }

function sanitizeString($var)
{
    $var = strip_tags($var);
    $var = stripslashes($var);
    $var = htmlentities($var);

    return mysql_real_escape_string($var);  
}

function queryMysql($query)
{
    $result = mysqli_query($query) or die(mysql_error());
    return $result; 
}


 $var1 = $_POST['VAR1'];
 $var2 = $_POST['VAR2'];
 $var3 = $_POST['VAR3'];



 $query = "INSERT INTO users (username, userpass, email)
 VALUES ('".$var1."','".$var2."' ,'".$var3."')";

 $result = mysqli_query($mysqli, $query); 

mysqli_close($mysqli);

echo $var1 ." ". $var2 ." ". $var3 ;

 $query = "SELECT FROM users";
 $result = mysqli_query($mysqli, $query);

?>

After $result = mysqli_query($mysqli, $query); Add this:

print '<table>'; // Up to you to put thead, tbody etc
while($row = $result->fetch_assoc()) {
    print '<tr>';
    print '<td>' . $row['username'] . '</td>'; 
    print '<td>' . $row['userpass'] . '</td>'; 
    print '<td>' . $row['email'] . '</td>'; 
    // And so on

    print '</tr>';
}
print '</table>';

But you should think about, if its a good idea to put everything in one file. It is better to separate Server Code from the HTML-Part.

Also the MVC Approach (Model View Controller) is interesting to know about, same thing for templating systems.

EDIT

Have a look at @Luke Madhanga 's comment!!