如何应用分页排序？

I tried applying sorting with paging but it is only sorting first page because the page number is one which is fine by me but the records of second and third page are not sorted.

Here is the FIRST PAGE CODE

include_once("session.php");
include_once("functions.php");
include_once("connection.php");

$username = $_SESSION["username"];


$orderby = "job_name";
$order = "asc";
//$conn2 = mysqli_connect("localhost","root","","jobportal");
//$conn3 = mysqli_connect("localhost","root","","jobportal");
//$conn4 = mysqli_connect("localhost","root","","jobportal");


$sql3 = "SELECT COUNT(*) FROM job_info WHERE username='$username' AND approved=1";
$sql4 = "SELECT COUNT(*) FROM job_info WHERE username='$username' AND approved=0";

$stmt3 = $conn->query($sql3);
$stmt4 = $conn->query($sql4);
$approved = $stmt3->fetch_array();
$pending = $stmt4->fetch_array();

$total_rows_approved = $approved[0];
$total_rows_pending = $pending[0];

$limit = 2;
$total_pages_apporved = ceil($total_rows_approved/$limit);
$total_pages_pending = ceil($total_rows_pending/$limit);
$page_approved = 0;
$page_pending = 0;
if(isset($_GET["page_approved"])){
    $page_approved = $_GET["page_approved"];
}
if($page_approved){
    $start_approved = ($page_approved-1)*$limit;
}
else{
    $start_approved = 0;
}

if(isset($_GET["page_pending"])){
    $page_pending = $_GET["page_pending"];
}
if($page_pending){
    $start_pending = ($page_pending-1)*$limit;
}
else{
    $start_pending = 0;
}

$sql1 = "select * from job_info where username='$username' and approved=1 order by ".$orderby." ".$order." limit $start_approved,$limit";
$stmt1 = $conn->query($sql1);

$sql2 = "select * from job_info where username='$username' and approved=0 order by ".$orderby." ".$order." limit $start_pending,$limit";
$stmt2 = $conn->query($sql2);

<script>
    var page_no_approved=1;
    var page_no_pending=1;
    function order_column1(column_name,column_order){
        $.ajax({
        url: "get_job_list.php",
        data: "orderby1="+column_name+"&order1="+column_order+"&page_no_approved="+page_no_approved,
        type: "POST",
        success: function(data){
            $("#showresults").html(data);
       }
    });
}
function order_column2(column_name,column_order){

    $.ajax({
    url: "get_job_list.php",
    data: "orderby2="+column_name+"&order2="+column_order+"&page_no_pending="+page_no_pending,
    type: "POST",
    success: function(data){
        $("#showresults").html(data);
    }
    });
}
</script>

and here is the SECOND PAGE CODE(ajax)

include_once("session.php");
include_once("functions.php");
include_once("connection.php");

$username = $_SESSION["username"];

$sql3 = "SELECT COUNT(*) FROM job_info WHERE username='$username' AND approved=1";
$sql4 = "SELECT COUNT(*) FROM job_info WHERE username='$username' AND approved=0";

$stmt3 = $conn->query($sql3);
$stmt4 = $conn->query($sql4);
$approved = $stmt3->fetch_array();
$pending = $stmt4->fetch_array();

$total_rows_approved = $approved[0];
$total_rows_pending = $pending[0];

$limit = 2;
$total_pages_apporved = ceil($total_rows_approved/$limit);
$total_pages_pending = ceil($total_rows_pending/$limit);
$page_approved = 0;
$page_pending = 0;
if(isset($_POST["page_no_approved"])){
    $page_approved = $_POST["page_no_approved"];
}
if($page_approved){
    $start_approved = ($page_approved-1)*$limit;
}
else{
    $start_approved = 0;
}

if(isset($_POST["page_no_pending"])){
    $page_pending = $_POST["page_no_pending"];
}
if($page_pending){
    $start_pending = ($page_pending-1)*$limit;
}
else{
    $start_pending = 0;
}

$orderby1 = "job_name";
$order1 = "asc";
$orderby2 = "job_name";
$order2 = "asc";

if(!empty($_POST["orderby1"])){
    $orderby1 = $_POST["orderby1"];
}
if(!empty($_POST["order1"])){
    $order1 = $_POST["order1"];
}

if(!empty($_POST["orderby2"])){
    $orderby2 = $_POST["orderby2"];
}
if(!empty($_POST["order2"])){
    $order2 = $_POST["order2"];
}

$date_order1 = "asc";
$job_name_order1 = "asc";
$industry_order1 = "asc";
$date_order2 = "asc";
$job_name_order2 = "asc";
$industry_order2 = "asc";

if($orderby1 == "date" && $order1=="asc"){
    $date_order1 = "desc";
}
if($orderby1 == "job_name" && $order1=="asc"){
    $job_name_order1 = "desc";
}
if($orderby1 == "industry" && $order1 == "asc"){
    $industry_order1 = "desc";
}
if($orderby2 == "date" && $order2=="asc"){
    $date_order2 = "desc";
}
if($orderby2 == "job_name" && $order2=="asc"){
    $job_name_order2 = "desc";
}
if($orderby2 == "industry" && $order2 == "asc"){
    $industry_order2 = "desc";
}

$sql1 = "select * from job_info where username='$username' and approved=1 order by ".$orderby1." ".$order1." limit $start_approved,$limit";
$result1 = $conn->query($sql1);

$sql2 = "select * from job_info where username='$username' and approved=0 order by ".$orderby2." ".$order2." limit $start_pending,$limit";
$result2 = $conn->query($sql2);

EDIT: I didn't included the code to display data because it will make the already large code to be more longer and possibly unreadable. It would help if someone could point me to the place where the concept of sorting with pagination is applied or if someone could explain the concept with small example.