问具有命名参数的PDO无效参数号？

EN

Final Class StageMapper Extends DataMapper
{
    public static function push($vendor)
    {
        $st = self::$db->prepare(
            'UPDATE footable SET site = :site, hash = :hash WHERE site = :site AND id = :id'
        );

        $st->execute(array(
            ':site'         => $vendor->s,
            ':hash'         => $vendor->h,
            ':uid'          => $vendor->i,
        ));
    }
}

// some rand vals
$vendor = (object) array (
  's'   => 'domain.com',
  'h'   => '180b35',
  'i'   => '1',
);

DataMapper::init();          // kick off a new connection via PDO
StageMapper::push($vendor);  // do stuff =P