on scroll load data

  <script type="text/javascript" src="jquery.js"></script>
  
  <script type="text/javascript">
  
  // $(document).height() is total height of current screen. 
  // scrollTop is scroll from top , if top to scroll & total height exists current window size
  
    $(window).scroll(function (){
       if($(document).height() <= $(window).scrollTop() + $(window).height()){
	   loadmore();
       }
    });

    function loadmore(){
      var val = document.getElementById("row_no").value;
        $.ajax({
          type: 'post',
          url: 'get_results.php',
          data: {
           getresult:val
          },
          success: function (response) {
            var content = document.getElementById("all_rows");
            content.innerHTML = content.innerHTML+response;
            document.getElementById("row_no").value = Number(val)+10;
          }
      });
    }
  </script>
  
<div id="all_rows">

    <?php

	mysql_connect('localhost','root','');
	mysql_select_db('demo');
	$select=mysql_query("select comment from sample_comment limit 0,10");
	while($row=mysql_fetch_array($select))
	{
	    echo "<p class='rows'>".$row['comment']."</p>";
	}
    ?>

</div>

<input type="hidden" id="row_no" value="10">