执行

foreach ( $results as $result ){    
       // code goes here ..
}
....

foreach ( $results as $result ){    
       // code goes here ..
}

是因为两次遍历pdo resultSet造成的，解决办法：

$records = array();

foreach ($results as $result)
{
    $records[] = $result;
}

This result is a forward only result set, calling rewind() after moving forward is not supported