CREATE TABLE user_vote(
user_ip VARCHAR(40),
vote TEXT);

<?php
$host = 'localhost';
$user = 'root';
$pass = '';
mysql_connect($host, $user, $pass);
mysql_select_db('demo');

if(isset($_POST[ 'vote_val' ]))
{
 $userip=$_SERVER['REMOTE_ADDR'];

 $checkip=" SELECT user_ip FROM user_vote WHERE user_ip='$userip' ";

 $query=mysql_query($checkip);

 if(mysql_num_rows($query)>0)
 {
  echo "You Already Post Your Vote";
 }
 else
 {
  $vote = $_POST[ 'vote_val' ];
  $insertdata=" INSERT INTO user_vote VALUES( '$userip','$vote' ) ";
  mysql_query($insertdata);
  echo "You Vote Is Successfully Inserted";
 }

 exit();
}
?>