<?php
//retrieve form variables
$isbn = $_POST['isbn'];
$author = $_POST['author'];
$title = $_POST['title'];
$price = $_POST['price'];
$page = $_POST['page'];
if (strlen($isbn) == 0 or strlen($author) == 0)
{ 
   echo "Go  back and fill all fields !";
   exit;
}
//connet to MySQL server
$db = mysql_connect();
if(!$db)
{
     echo " Error : cannot open connection.";
     exit;
}
mysql_select_db('publisher');
$query = " insert into books 
                (isbn, author, title, price, page) values
                ('".$isbn."', '". $author."', '".$title."' ,'".$price."' ,  '".$page."' )";
$result = mysql_query($query);
if($result)
   echo mysql_affected_rows(). '<b> book inserted into database.</b>';
mysql_close($db);
?>