YA: Simple Login Check

<?php
// In response to a Yahoo Answer's question
session_start();

$username = $_POST['username'];
$password = $_POST['password'];

if ($username && $password){
    $connect = mysql_connect("localhost", "par24_user", "*password*") or die("Couldn't Connect!");
    mysql_select_db("par24_user")or die ("Couldn't find db!");

    $username = mysql_real_escape_string($username);
    $password = md5($password);

    $result = mysql_query( "SELECT username FROM user WHERE username='" . $username . "' AND password='" . $password . "' LIMIT 1");

    if($result && mysql_num_rows($result) > 0){
        $_SESSION['username'] = mysql_fetch_object($result)->username;
        echo "You've Logged on! <a href='member.php'</a> Click here to eneter member page.";
    }else{
        echo 'Invalid Username/Password Combination. <a href="' . $_SERVER['HTTP_REFERER'] . '">Click To Return</a>';
    }
} else {
    die ("Please enter a username and password!");
}

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