<?php
include '../include/conf.php';
$session_id = $_POST['session_id'];
$product_id = $_POST['product_id'];
$get_q = mysqli_query($conn, "select * from shop_cart where productid = '$product_id' and session_id = '$session_id'");
$check_rows = mysqli_num_rows($get_q);
if($check_rows > 0){
$get_qty = mysqli_fetch_array($get_q, MYSQLI_ASSOC);
echo $get_qty['qty'];
}else{
    echo '0';
}
?>