Add access to poll_choice data

I've created a view in order to display two pages : last polls, and most voted polls.
For the second one, I need to access in views_ui to the field chvotes of table poll_choice to compute the total amount of votes (using agregation), my sort criterion.
But the fields of poll_choice aren't available in views_ui (not declared in poll.views.inc poll_views_data()).

To do this I've implemented the hook_views_data() hook in a custom module, following the example given in http://api.drupal.org/api/views/views.api.php/function/hook_views_data/7 :

function mymodule_views_data() {
/*
CREATE TABLE `poll_choice` (
 `chid` int(10) unsigned NOT NULL AUTO_INCREMENT COMMENT 'Unique identifier for a poll choice.',
 `nid` int(10) unsigned NOT NULL DEFAULT '0' COMMENT 'The node.nid this choice belongs to.',
 `chtext` varchar(128) NOT NULL DEFAULT '' COMMENT 'The text for this choice.',
 `chvotes` int(11) NOT NULL DEFAULT '0' COMMENT 'The total number of votes this choice has received by all users.',
 `weight` int(11) NOT NULL DEFAULT '0' COMMENT 'The sort order of this choice among all choices for the same node.',
 PRIMARY KEY (`chid`),
 KEY `nid` (`nid`)
) ENGINE=InnoDB AUTO_INCREMENT=27 DEFAULT CHARSET=utf8 COMMENT='Stores information about all choices for all polls.'
*/

  $data['poll_choice']['table']['group'] = t('Poll');

  $data['poll_choice']['table']['join'] = array(
    'node' => array(
      'left_field' => 'nid', 
      'field' => 'nid',
    ),
  );

  // PK `chid` int(10) unsigned NOT NULL AUTO_INCREMENT COMMENT 'Unique identifier for a poll choice.',
  $data['poll_choice']['chid'] = array(
    'title' => t('Poll choice unique identifier (chid)'), 
    'help' => t('Unique identifier for a poll choice.'),
    'field' => array(
      'handler' => 'views_handler_field_numeric', 
      'click sortable' => TRUE,
    ), 
    'filter' => array(
      'handler' => 'views_handler_filter_numeric',
    ), 
    'sort' => array(
      'handler' => 'views_handler_sort',
    ),
  );

  // `nid` int(10) unsigned NOT NULL DEFAULT '0' COMMENT 'The node.nid this choice belongs to.',
  $data['poll_choice']['nid'] = array(
    'title' => t('Poll choices'), // apparaît dans la liste des relations
    'help' => t('The node.nid this choice belongs to.'),
    );

  // `chtext` varchar(128) NOT NULL DEFAULT '' COMMENT 'The text for this choice.',
  $data['poll_choice']['chtext'] = array(
    'title' => t('Choice label'), 
    'help' => t('The text for this choice.'), 
    'field' => array(
      'handler' => 'views_handler_field', 
      'click sortable' => TRUE, // This is use by the table display plugin.
    ), 
    'sort' => array(
      'handler' => 'views_handler_sort',
    ), 
    'filter' => array(
      'handler' => 'views_handler_filter_string',
    ), 
    'argument' => array(
      'handler' => 'views_handler_argument_string',
    ),
  );

  // `chvotes` int(11) NOT NULL DEFAULT '0' COMMENT 'The total number of votes this choice has received by all users.',
  $data['poll_choice']['chvotes'] = array(
    'title' => t('Number of votes for the choice'), 
    'help' => t('The total number of votes this choice has received by all users.'), 
    'field' => array(
      'handler' => 'views_handler_field_numeric', 
      'click sortable' => TRUE,
    ), 
    'filter' => array(
      'handler' => 'views_handler_filter_numeric',
    ), 
    'sort' => array(
      'handler' => 'views_handler_sort',
    ),
  );

  // `weight` int(11) NOT NULL DEFAULT '0' COMMENT 'The sort order of this choice among all choices for the same node.',
  $data['poll_choice']['weight'] = array(
    'title' => t('Choice weight'), 
    'help' => t('The sort order of this choice among all choices for the same node.'), 
    'field' => array(
      'handler' => 'views_handler_field_numeric', 
      'click sortable' => TRUE,
    ), 
    'filter' => array(
      'handler' => 'views_handler_filter_numeric',
    ), 
    'sort' => array(
      'handler' => 'views_handler_sort',
    ),
  );
  
  return $data;
}

It seems to work fine, and I achieved to get the list of polls ordered by number of votes, using agregation.
Perhaps it would be useful for other users to have this implemeted in the views module.