Loading current user from database - php

Question

So I have a table named realtimeusage it contains ID, KWH, UnitValue, AccessTIME I want to fetch usage only for the Current user by his "id" any suggestion for my code
<?php
session_start();
require_once('connect.php');
$_SESSION['id'] = $id;
// For display Current user realtimeusage
$displayquery = "SELECT * ";
$displayquery .= "FROM realtimeusage WHERE `id` = '".$_SESSION['id']."'";
$displayresult = mysqli_query($connection, $displayquery);
if (!$displayresult){
die("database query failed");
}
?>
the table to fetch data:
<table>
<thead>
<tr>
<th> AccountID</th>
<th> KWH</th>
<th>UnitValue</th>
<th>AccessTIME</th>
</tr>
</thead>
<tbody>
<?php
while ($rows= mysqli_fetch_assoc($displayresult)) {
?>
<!--id-->
<td><?php echo $rows["ID"]; ?></td>
<!--User name-->
<td><?php echo $rows["KWH"]; ?></td>
<!--Full name-->
<td><?php echo $rows["UnitValue"]; ?></td>
<!-- Roles-->
<td><?php echo $rows["AccessTIME"]; ?></td>
</tbody>
<?php } ?>
</table>
when I run this code it shows all usage in the table
<?php
session_start();
require_once('connect.php');
$username = $_SESSION['username'];
$roles = $_SESSION['roles'];
// For display realtimeusage
$displayquery = "SELECT * ";
$displayquery .= "FROM realtimeusage";
$displayresult = mysqli_query($connection, $displayquery);
if (!$displayresult){
die("database query failed");
}
?>

Answer 1

From where are you getting the value of id? I guess id is in $_SESSION['id'], if user is logged in, and to use that id you need to change the assignment statement as
$id=$_SESSION['id'];
And use $id in query
$displayquery .= "FROM `realtimeusage` WHERE `id` = '".$id."'";