下拉选择分页页面

I'm working right now in Dropdownlist pagination. But the problem is I don't know the next step that I'm going to do.

Here's the script. The dropdownlist value is correct, but I don't know how to finish this script. What I need is when I select in pagination dropdown it show the records base on itemperpage. But this script is not working.

$('#pageNo').on('change', function(){
    var loadPage = $('#pageNo').val();
    // Do your page submit to load another page
});

get.php

<?php
$mysqli = new mysqli("localhost", "root", "", "app");

$id = $mysqli->real_escape_string($_GET["q"]);//used for Dynamic Dropdown  

$id2 = $mysqli->real_escape_string($_GET["id"]); // used for PHP pagination

$sql = $mysqli->query("SELECT * FROM app ORDER BY id ASC");  
$nr = mysqli_num_rows($sql); 

$itemsPerPage = 100; 

$page_count = ($nr / $itemsPerPage) + 1;

echo"<select id='pageNo'>";
        for($y=1; $y < $page_count; $y++) {
            echo "<option value='".$y."'>".$y."</option>";
        }
echo'</select>';
?>

Select.php

<script>
function showUser(str,ids) {
    var $txtHint = $('#txtHint');
    if (str=="" || ids=="") {
        $txtHint.html('');
        return;
    }
    $txtHint.load('get.php?q='+str+'&id='+ids)  
}

</script>
<body onload=showUser(str="ALL")>

<select name="drop_1" id="drop_1" onchange="showUser(this.value)" style="overflow:scroll;width:100px;">
        <option value="ALL" selected='ALL'>ALL</option>
        <?php getTierOne(); ?>
</select>
<div id="txtHint"></div>

Probably easier to do it in your sql

 $sql = $mysqli->query("SELECT * FROM app ORDER BY id ASC LIMIT ".$pagenum*100.",100");