我们常见给产品进行5星评价的系统，我初步的构想如下，

SELECT avg(vote) FROM votes WHERE gid = $gid;
SELECT count(uid) FROM votes WHERE gid = $gid;

CREATE TABLE IF NOT EXISTS `games` (
  `id` int(8) NOT NULL auto_increment,
  `title` varchar(50) NOT NULL,
  PRIMARY KEY  (`id`)
) AUTO_INCREMENT=1 ;

CREATE TABLE IF NOT EXISTS `users` (
  `id` int(8) NOT NULL auto_increment,
  `username` varchar(20) NOT NULL,
  PRIMARY KEY  (`id`)
) AUTO_INCREMENT=1 ;

CREATE TABLE IF NOT EXISTS `votes` (
  `uid` int(8) unsigned NOT NULL,
  `gid` int(8) unsigned NOT NULL,
  `vote` int(1) NOT NULL,
  PRIMARY KEY (`gid`, `uid`)
) ;

如何修改更高效？
例如，
当数据上万时，把平均值存储下来，而不是每次都进行计算？
在games表中进行适当的冗余，增加一个评论加1？
我现在有点拿不定主意。

CREATE TABLE IF NOT EXISTS `games` (
  `id` int(8) NOT NULL auto_increment,
  `title` varchar(50) NOT NULL,
 `vote_1` int(8) unsigned NOT NULL,
`vote_2` int(8) unsigned NOT NULL,
`vote_3` int(8) unsigned NOT NULL,
`vote_4` int(8) unsigned NOT NULL,
`vote_5` int(8) unsigned NOT NULL,
`avgrate` int(8) unsigned NOT NULL,
  PRIMARY KEY  (`id`)
) AUTO_INCREMENT=1 ;