function post_array($table=NULL, $data=array(), $xss_clean = FALSE)
	{
		if(empty($data)) return FALSE;

		$fields = $this->fields($table);

		foreach ($data as $k => $v)
		{
			if(in_array($k, $fields) == FALSE)
			{
				unset($data[$k]);
			}
			else
			{
				if($xss_clean === TRUE)
				{
					$data[$k] = $this->input->xss_clean($v);
				}
			}
		}

		return $data;
	}

	function fields($table=NULL)
	{
		return $this->db->list_fields($table);
	}