Jquery vote

Jquery vote helps you to display user votes on blog post. Here is the Database Design

Messages Table :

CREATE TABLE messages(
mes_id INT PRIMARY KEY AUTO_INCREMENT,
msg TEXT,
up INT,
down INT);

Voting_IP Table : Storing IP address
CREATE TABLE Voting_IP(
ip_id INT PRIMARY KEY AUTO_INCREMENT,
mes_id_fk INT,
ip_add VARCHAR(40),
FOREIGN KEY(mes_id_fk)
REFERENCES messages(mes_id));

Here is the class name of anchor tag. Using element.attr("id") calling vote button value(messsage Id):

<script type="text/javascript" src="http://ajax.googleapis.com/ajax/
libs/jquery/1.3.0/jquery.min.js"></script>
<script type="text/javascript">
$(function() {
$(".vote").click(function()
{
var id = $(this).attr("id");
var name = $(this).attr("name");
var dataString = 'id='+ id ;
var parent = $(this);

if (name=='up')
{
$(this).fadeIn(200).html('<img src="dot.gif" />');
$.ajax({
type: "POST",
url: "up_vote.php",
data: dataString,
cache: false,

success: function(html)
{
parent.html(html);
}
});
}
else
{
$(this).fadeIn(200).html('<img src="dot.gif" />');
$.ajax({
type: "POST",
url: "down_vote.php",
data: dataString,
cache: false,

success: function(html)
{
parent.html(html);
}
});
}
return false;
});
});
<script

//HTML Code

<?php
include('config.php');
$sql=mysql_query("SELECT * FROM messages LIMIT 9");
while($row=mysql_fetch_array($sql))
{
$msg=$row['msg'];
$mes_id=$row['mes_id'];
$up=$row['up'];
$down=$row['down'];
?>
<div class="main">
<div class="box1">
<div class='up'>
<a href="" class="vote" id="<?php echo $mes_id; ?>" name="up">
<?php echo $up; ?></a></div>

<div class='down'>
<a href="" class="vote" id="<?php echo $mes_id; ?>;" name="down">
<?php echo $down; ?></a></div>
</div>

<div class='box2' ><?php echo $msg; ?></div>
</div>

<?php } ?>



Contains PHP code:

<?php
include("config.php");
$ip=$_SERVER['REMOTE_ADDR'];

if($_POST['id'])
{
$id=$_POST['id'];
$id = mysql_escape_String($id);
//Verify IP address in Voting_IP table
$ip_sql=mysql_query("select ip_add from Voting_IP where mes_id_fk='$id' and ip_add='$ip'");
$count=mysql_num_rows($ip_sql);

if($count==0)
{
// Update Vote.
$sql = "update Messages set up=up+1 where mes_id='$id'";
mysql_query( $sql);
// Insert IP address and Message Id in Voting_IP table.
$sql_in = "insert into Voting_IP (mes_id_fk,ip_add) values ('$id','$ip')";
mysql_query( $sql_in);
echo "<script>alert('Thanks for the vote');</script>";
}
else
{
echo "<script>alert('You have already voted');</script>";
}

$result=mysql_query("select up from Messages where mes_id='$id'");
$row=mysql_fetch_array($result);
$up_value=$row['up'];
echo $up_value;

}
?>