public function update(array $data = array(), array $criteria = array())
    {
        $this->viewCheck(__FUNCTION__);

        $data = array_merge(
            array_filter($this->_schema['others'], array($this, 'filterRule')),
            $data);

        $params = array();
        $values = array_filter($this->_schema['values']);
        $others = array_filter($this->_schema['others']);
        foreach ($data as $key => $value)
            if (is_array($value))
                return false;
            elseif (isset($this->_properties['fields'][$key]))
                if (isset($values[$key]) && isset($others[$key])
                    && $values[$key]==$others[$key]
                )
                    continue;
                else
                    $params[':'.$key] = $value;

        if (empty($params))
            return true;

        $query = $this->buildUpdate($params, $criteria);

        if (!($query && $this->validate($params)))
            return false;

        $old = clone $this;
        if (!$this->beforeUpdate($params))
            return false;

        if ($result = $this->run($query, $params))
            $this->assign($params);

        if (!$this->afterUpdate($old))
            return false;

        return $result;
    }