users.php

<?php
    session_start();
    include_once "config.php"; // Include the config file to establish a database connection
    $outgoing_id = $_SESSION['unique_id'];
    $sql = mysqli_query($conn, "SELECT * FROM users");
    $output = " ";

    if(mysqli_num_rows($sql) == 1){
        $output .="No users are available to chat";
    } elseif(mysqli_num_rows($sql) > 0){
        include "data.php";
    }
    echo $output;
?>