PHP数据库PDO连接

嘿，伙计们，我在php的PDO有一点麻烦，因为它返回的错误是一个未定义的索引。函数、查询和返回结果的代码如下:

function getUserDetails($user) {
   $db = connect();
try {
    $stmt = $db->prepare('SELECT name,addr AS address,team
FROM TreasureHunt.Player LEFT OUTER JOIN TreasureHunt.MemberOf ON (name=player) 
LEFT OUTER JOIN TreasureHunt.PlayerStats USING (player)
WHERE name=:user');
    $stmt->bindValue(':user', $user, PDO::PARAM_STR);
    $stmt->execute();
    $results = $stmt->fetchAll();
    $stmt->closeCursor();
} catch (PDOException $e) { 
    print "Error : " . $e->getMessage(); 
    die();
}
return $results;  
}

然而，当运行代码的索引页，我得到一个错误，说通知:未定义的索引:名称

索引的代码是:

try {
$details = getUserDetails($_SESSION['player']);
echo '<h2>Name</h2> ',$details['name'];
echo '<h2>Address</h2>',$details['address'];
echo '<h2>Current team</h2>',$details['team'];
echo '<h2>Hunts played</h2> ',$details['nhunts'];
echo '<h2>Badges</h2>';
foreach($details['badges'] as $badge) {
    echo '<span class="badge" title="',$badge['desc'],'">',$badge['name'],'</span><br />';
}
} catch (Exception $e) {
echo 'Cannot get user details';
}

我的问题是为什么它抛出一个通知，我如何解决这个问题?