Insert Record into Mysql without refreshing?

<?php
/////////This is addfavorites.php
include_once ("/home/xxxxxx/public_html/xxxxxx/auth.php");
include_once ("/home/xxxxxx/public_html/xxxxxx/authconfig.php");
include_once ("/home/xxxxxx/public_html/xxxxxx/check.php");
	
	$username = $check["uname"];	
	$sql = "INSERT INTO favorites (id,username,mls) VALUES (NULL,'$username','$MLS_ACCT')";
	$result = mysql_query($sql)
?>
 
Below is the search engine page where I want to add the favorites.
 
<a class="pagination" href="http://www.xxxxxx.com/search.php">Start New Search</a><br />
<br />
<?
include ('sqlinfo.php');
$result = mysql_query($query);
$i = 0;
	     	function para_limit($string,$len) {
 			$words = explode(" ",$string);
		    $within = array_slice($words,0,$len);
		    $output = implode(" ",$within);
		    $output .= "...";
			return $output;
			}
    while($row =mysql_fetch_array($result)) {
    $CURRENT_PRICE = $row['CURRENT_PRICE'];
	$BEDROOMS = $row['BEDROOMS'];
	$BATHS = $row['BATHS'];
	$ZIP = $row['ZIP'];
	$SUBDIVISION = $row['SUBDIVISION'];
	$ACREAGE = $row['ACREAGE'];
	$STATE = $row['STATE'];
	$CITY = $row['CITY'];
	$MLS_ACCT = $row['MLS_ACCT'];
	$MEDIA_REMARKS = $row['MEDIA_REMARKS'];
	$FTR_SUBSTRUC = $row['FTR_SUBSTRUC'];
	$HIGH_SCHOOL = $row['HIGH_SCHOOL'];
	$UDF_PHOTO0 = $row['UDF_PHOTO0'];	
	$images = $UDF_PHOTO0;
    $arr_images = explode(",",$images);
	
?>
<br />
<br />
<table width="730" border="0" align="center" cellpadding="0" cellspacing="0" class="results">
  <tr>
    <td width="265" height="192" rowspan="2" align="left" valign="top"><?
		    if (isset($arr_images[0]))
		    echo "<a href=\"search_flyer.php?MLS_ACCT=$MLS_ACCT\" target=\"_blank\" style=\"border: solid 2px #e9e9e9;\"><img src=\"http://www.xxxxxx.com/huntsvillehomes/$arr_images[0]\" width=\"256\" height=\"192\" border=\"0\"></a>";
			else { print "<img src=\"images/na.gif\" width=\"256\" height=\"192\" style=\"border: solid 2px #e9e9e9;\">"; }
		    ?>
      </span></td>
    <td width="90" align="left" valign="top"><strong>Subdivision:<br />
      Bedrooms:<br />
      Total Baths:<br />
      Acreage:<br />
      Foundation:<br />
      High School:</strong><br />
      <br />
      <div align="left" style="line-height:30px;"><a class="boxy" href="http://www.xxxxxx.com/search_flyer.php?MLS_ACCT=<?=$MLS_ACCT?>" target="_blank">VIEW DETAILS</a><br />
      </div></td>
    <td width="196" align="left" valign="top"><?=$SUBDIVISION?>
      <br />
      <?=$BEDROOMS?>
      <br />
      <?=$BATHS?>
      <br />
      <?=$ACREAGE?>
      <br />
      <?=$FTR_SUBSTRUC?>
      <br />
      <?=$HIGH_SCHOOL?>
      <br />
      <br /></td>
    <td colspan="2" align="right" valign="top" style="border-left: solid 1px #cccccc;"><a class="a2" href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&msa=0&om=1&msid=101482284079313509961.000001132d2073ea2a920&ll=34.712831,-86.743927&spn=0.393974,0.63858&z=11" target="_blank"><? print $CITY . ',&nbsp;' . $STATE . '&nbsp;' . $ZIP?></a><br />
      <span style="font-size: 16px; font-weight: bold;"><? print "$" .number_format($CURRENT_PRICE, 0, '.', ',') ; ?></span><br />
      
<!-----HERE IS THE LINK WHERE I WANT TO ADD IT-------->
<a href="addfavorite.php?MLS_ACCT=<?=$MLS_ACCT?>"> <img src="http://www.xxxxxx.com/images/addtofavorites.gif" /></a> <br />
    </td>
  </tr>
  <tr>
    <td colspan="2" align="left" valign="bottom"><?
			  $insurance = .00035 * $CURRENT_PRICE;
			  $taxes = .000321 * $CURRENT_PRICE;
			  $mi = $CURRENT_PRICE * .00040833;
			  $pow = pow((1 + (6 / 1200)), (30 * 12)); 
				$payment = ($CURRENT_PRICE * $pow) * (6 / 1200) / ($pow - 1)  ;
				$total = ((.00035 * $CURRENT_PRICE) + (.000321 * $CURRENT_PRICE) + ($CURRENT_PRICE * .00040833) + (($CURRENT_PRICE * $pow) * (6 / 1200) / ($pow - 1)));
			  ?>
      </span>
      <!--Appx Principal &amp; Interest: <? print "$" .number_format($payment, 0, '.', ',') ;?><br />
			  Mortgage Insurance (If Needed): <? print "$" .number_format($mi, 0, '.', ',') ; ?><br />
			  Appx Monthly Insurance: <? print "$" .number_format($insurance, 0, '.', ',') ; ?><br />
              Appx Monthly Taxes: <? print "$" .number_format($taxes, 0, '.', ',') ; ?><br /> --->
      <span style="font-weight: bold; font-size: 10px">Appx Total Monthly Payment:</span><span style="font-weight: bold; font-size: 10px"></span><span style="font-weight: bold"> <? print "$" .number_format($total, 0, '.', ',') ;?></span><br />
      <span style="font-size: 10px">*Includes Appx. Taxes, Insurance, and Mortgage Insurance.</span> &nbsp;</td>
    <td width="97" align="right" valign="bottom" style="border-left: solid 1px #cccccc;"><img src="http://www.level10realty.com/images/nalmls.jpg" alt="Nalmls Listing" width="80" height="28" /><br />
      IDX Listing Feed</td>
    <td width="82" align="right" valign="bottom">Listing ID:<br />
      <span class="mlsid">
      <?=$MLS_ACCT?>
      </span></td>
  </tr>
</table>
<?
$i++;
} 
?>
                                              

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function pass(income)
{
   xmlHttp=ajax();
   if (xmlHttp==null)
   {
    alert (Your browser doesnt support AJAX!');
    return;
    }
	var myVar = income; 
    var url='update.php';
    var sc ='myVar='+myVar;
    xmlHttp.open('POST', url, true);
    xmlHttp.setRequestHeader('If-Modified-Since', 'Sat, 1 Jan 2000 00:00:00 GMT');
    xmlHttp.setRequestHeader('Content-Type','application/x-www-form-urlencoded; charset=UTF-8');
    xmlHttp.setRequestHeader('Content-length', sc.length);
    xmlHttp.setRequestHeader('Connection', 'close');
    xmlHttp.onreadystatechange=updt();
    xmlHttp.send(sc);
}
 
function updt()
{
    if (xmlHttp.readyState==4 && xmlHttp.status == 200)
    {
        document.getElementById('result').innerHTML=xmlHttp.responseText;
    }
}
function ajax()
{
    var xmlHttp=null;
    try
    {
        // Firefox, Opera 8.0+, Safari
        xmlHttp=new XMLHttpRequest();
    }
    catch (e)
    {
        // Internet Explorer
        try
        {
            xmlHttp=new ActiveXObject('Msxml2.XMLHTTP');
        }
        catch (e)
        {
            xmlHttp=new ActiveXObject('Microsoft.XMLHTTP');
        }
    }
    return xmlHttp;
} 
                                              

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function pass(income,income2)
{
   xmlHttp=ajax();
   if (xmlHttp==null)
   {
    alert (Your browser doesnt support AJAX!');
    return;
    }
    var myVar = income; 
    var myVar2 = income2;
    var url='update.php';
    var sc ='myVar='+myVar+'&myVar2='+myVar2;
    xmlHttp.open('POST', url, true);
    xmlHttp.setRequestHeader('If-Modified-Since', 'Sat, 1 Jan 2000 00:00:00 GMT');
    xmlHttp.setRequestHeader('Content-Type','application/x-www-form-urlencoded; charset=UTF-8');
    xmlHttp.setRequestHeader('Content-length', sc.length);
    xmlHttp.setRequestHeader('Connection', 'close');
    xmlHttp.onreadystatechange=updt();
    xmlHttp.send(sc);
}
                                              

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