public static function delete($idpEntityId, $spEntityId, $user)
{
assert('is_string($idpEntityId)');
assert('is_string($spEntityId)');
assert('is_string($user)');
$store = self::getStore();
$params = array('_idp' => $idpEntityId, '_sp' => $spEntityId, '_user' => $user);
$query = 'DELETE FROM ' . $store->prefix . '_saml_PersistentNameID WHERE _idp = :_idp AND _sp = :_sp AND _user = :_user';
$query = $store->pdo->prepare($query);
$query->execute($params);
}