Is this secure enough?

I'm new with PDO, and I just wanted to know if this code:

$string = $_POST['string'];
$matches = $SQL->prepare("SELECT * FROM `users` WHERE `name` LIKE ?");
$matches->execute(array('%'.$string.'%'));

foreach($matches->fetchAll() as $match) {
    echo $match["name"开发者_开发问答]."<br/>";
}

Is secure enough? I just wan't to be sure and prevent from hacking. This code will withdraw all users from the database with name like in the $string variable.

Feel free to post your solutions also!

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PDO will automatically escape any input given to it before executing the query, so in terms of an SQL injection attack, it is safe.