This should accomplish what you are setting out to do.
<?php
$con = mysql_connect("localhost","a7068104_user2","wiseguy1345");
if(!$con) {
die("could not connect to localhost:" .mysql_error());
}
header("refresh:1.5; url=NamesAction.php");
mysql_select_db("a7068104_world") or die("Cannot connect to database");
$fullname = mysql_real_escape_string($_POST['firstname'] . " " . $_POST['lastname']);
$query = "SELECT * FROM names_1 WHERE fullname='" . $fullname . "'";
$result = mysql_query($query);
if(mysql_num_rows($result) > 0 ){
echo "Your full name is already in the database and will not be added again!";
}
else {
$query = "INSERT INTO names_1 (firstname, lastname, fullname, age) VALUES('" . $_POST['firstname'] . "','" . $_POST['lastname'] . "','" . $fullname . "'," . $_POST['age'] . ")";
$result = mysql_query($query);
}
mysql_close($con);
?>
<html>
<head>
<link rel="stylesheet" href="Site.css"/>
<?php include("Header.php"); ?>
</head>
<body>
<div id="main">
<h1>Names</h1>
<p>You will be redirected back to the <b>Names</b> page in a moment.</p>
<?php include("Footer.php");?>
</div>
</body>
</html>