AJAX feature to retrieve user information (from my personal website, which I'm writing in PHP)

application.js

jQuery(document).ready(function() 
{
  var hideDelay = 500;  
  var userID;
  var hideTimer = null;

  // One instance that's reused to show info for the current person
  var container = jQuery('<div id="personPopupContainer">'
      + '<table width="" border="0" cellspacing="0" cellpadding="0" align="center" class="personPopupPopup">'
      + '<tr>'
      + '   <td class="corner topLeft"></td>'
      + '   <td class="top"></td>'
      + '   <td class="corner topRight"></td>'
      + '</tr>'
      + '<tr>'
      + '   <td class="left">&nbsp;</td>'
      + '   <td><div id="personPopupContent"></div></td>'
      + '   <td class="right">&nbsp;</td>'
      + '</tr>'
      + '<tr>'
      + '   <td class="corner bottomLeft">&nbsp;</td>'
      + '   <td class="bottom">&nbsp;</td>'
      + '   <td class="corner bottomRight"></td>'
      + '</tr>'
      + '</table>'
      + '</div>');

  jQuery('body').append(container);

  jQuery('.personPopupTrigger').live('click', function()
  {
      // format of 'rel' tag: userId from Books table
      //var settings = jQuery(this).attr('rel');
      userID = jQuery(this).attr('rel');
	  
	  // If no id in url rel tag, don't popup blank
      if (userID == '')
          return;
		
      if (hideTimer)
          clearTimeout(hideTimer);

      var pos = jQuery(this).offset();
      var width = jQuery(this).width();
      container.css({
          left: (pos.left + width + 35) + 'px',
          top: pos.top - 15 + 'px'
      });
		
      jQuery.ajax({  
          type: 'GET',  
          cache: false,
	  //dataType: (jQuery.browser.msie) ? "text" : "xml",
          url: 'sellerinfo.php',
	  data: "userID=" + userID,  
	  success: function(data)  
          {    
	       // Verify requested person is this person since we could have multiple ajax  
              // requests out if the server is taking a while.  
               if (userID > 0)  
              {	
               jQuery('#personPopupContent').html('<span style="line-height: 1em;">' + data + '</span>');  
              }  
          }  
                });  
	  container.css('display', 'block');
	});

  jQuery('.personPopupTrigger').live('mouseout', function()
  {
      if (hideTimer)
          clearTimeout(hideTimer);
      hideTimer = setTimeout(function()
      {
          container.css('display', 'none');
      }, hideDelay);
  });

  // Allow mouse over of details without hiding details
  jQuery('#personPopupContainer').mouseover(function()
  {
      if (hideTimer)
          clearTimeout(hideTimer);
  });

  // Hide after mouseout
  jQuery('#personPopupContainer').mouseout(function()
  {
      if (hideTimer)
          clearTimeout(hideTimer);
      hideTimer = setTimeout(function()
      {
          container.css('display', 'none');
      }, hideDelay);
  });
  
});

page.html

<a class='personPopupTrigger' id='sellerinformation' rel='".$userId."'>
Seller Info
</a>

sellerinfo.php

<?php
$userID = $_GET['userID'];

// connection settings stored in file
include("connectionParameters.php");
	
$connection = mysql_connect($host,$user,$pass)
	or die ("We're sorry, there seems to be an error. Please try again later.");

mysql_select_db($database);
	
$sql="SELECT * FROM Users WHERE userId = '.$userID.'";

$result = mysql_query($sql);

while($row = mysql_fetch_array($result))
  {	  
  echo "<div id='personPopupContent'>";

  echo "<p style='font-size: 12px;'><b>First name:</b> ".$row["firstName"]."</p>";
  //echo "<br/>";
  echo "<p style='font-size: 12px;'><b>School:</b> ".$row["university"]."</p>";
  //echo "<br/>";
  if($row["phone"] == ""){
	  echo "";}
  else{
  echo "<p style='font-size: 12px;'><b>Phone:</b> ".$row["phone"]."</p>";
  //echo "<br/>";
  }
  echo "<div style='font-size: 12px; width: 175px;'><b>Email:</b><span style='width: 170px;'> ".$row["email"]."</span></div>";
  
  echo "</div>";

  }

mysql_close($con);
?>