网站在首次刷新时不更新内容

Question

On my website I'm listing data from the database with the use of $query->fetch(PDO::FETCH_ASSOC);. Everything is working fine except that after changing the database and redirecting with header() the user must refresh the page again to actually see the changes. I don't know what is causing this and it seems odd that the content is there but only upon a second refresh. Any help would be great. Thanks.

This is the code that is listing data back to the user.

public function getCoilInfo ($coil_id) {
    //Database Connection
    $db = Database::getInstance();

    //Query to select all information from `coils` tables based off $coil_id
    $query = $db->getConnection()->prepare("SELECT * FROM `coils` WHERE coil_id = :coil_id");
    $query->execute(array(
        ':coil_id' => $coil_id
    ));

    //Return array with results
    return $query->fetch(PDO::FETCH_ASSOC);
}

I then reference the following class like this:

$coil = new Coil();
$coilInfo = $coil->getCoilInfo($_GET['coil_id']);

echo $coilInfo['coil_name'];