作者：zhanhailiang 日期：2014-12-02

本文将讲解如何基本Redis Sorted Set实现排行榜功能？

首先，请参见Redis数据类型：http://redis.cn/topics/data-types.html

如上所见，Redis有序集合非常适用于有序不重复数据的存储，例如游戏开发中无处不在的排行榜，如等级排行榜，经验排行榜，积分排行榜，历史筹码排行榜等。如果沿用传统的方法，一般是通过后端的定时任务去跑数据来生成排行榜数据，这种方法一方面无法满足产品对功能实时性的要求，另一方面也一定程度上消耗服务器端有限的资源。

以下举例说明如何实现一个积分排行榜：

1. 生成排行榜：

<?php
// vim: set expandtab cindent tabstop=4 shiftwidth=4 fdm=marker:
 
/**
 * @file     initRank.php
 * @version  1.0
 * @author   wade
 * @date     2014-12-02 21:26:11
 * @desc     本文讲述如何基本redis有序集合生成游戏排行榜数据
 */
 
$redis = new Redis();
$redis->connect(‘127.0.0.1‘, ‘6379‘);
 
$scoreKey = ‘user:score‘;
 
// init rank
$uidList = range(10000, 20000); // 初始化列表
shuffle($uidList);
foreach ($uidList as $uid) {
    $score = mt_rand(1, 10000000);
    $redis->zAdd($scoreKey, $score, $uid);
}

2. 获取排行榜前50名数据：

<?php
// vim: set expandtab cindent tabstop=4 shiftwidth=4 fdm=marker:
 
/**
 * @file     initRank.php
 * @version  1.0
 * @author   wade
 * @date     2014-12-02 21:26:11
 * @desc     本文讲述如何基本redis有序集合生成游戏排行榜数据
 */
 
$redis = new Redis();
$redis->connect(‘127.0.0.1‘, ‘6379‘);
 
$scoreKey = ‘user:score‘;
 
// get top 50
// zrange user:score -50 -1 withscores
$top50List = $redis->zRange($scoreKey, -50, -1, TRUE);
var_export($top50List);

查看输出的积分排行榜前50名用户数据如下：

[root@~/wade/codeReview/generate-rank-with-redis-sorted-set]# /usr/local/php/bin/php rank.php 
array (
  13297 => ‘9951424‘,
  17470 => ‘9951938‘,
  17397 => ‘9952228‘,
  19427 => ‘9953388‘,
  16800 => ‘9953838‘,
  19573 => ‘9954141‘,
  10100 => ‘9954436‘,
  11310 => ‘9955425‘,
  19995 => ‘9955665‘,
  12099 => ‘9959696‘,
  11619 => ‘9962507‘,
  17208 => ‘9962572‘,
  15769 => ‘9963074‘,
  19104 => ‘9963218‘,
  16343 => ‘9965226‘,
  11645 => ‘9965375‘,
  13185 => ‘9965506‘,
  18588 => ‘9968756‘,
  19764 => ‘9968885‘,
  13172 => ‘9969011‘,
  18031 => ‘9970756‘,
  10349 => ‘9971091‘,
  14612 => ‘9972515‘,
  17465 => ‘9974447‘,
  15812 => ‘9974457‘,
  10341 => ‘9974813‘,
  15415 => ‘9974895‘,
  12187 => ‘9974950‘,
  12426 => ‘9978519‘,
  13607 => ‘9979284‘,
  11375 => ‘9980609‘,
  10921 => ‘9981700‘,
  16360 => ‘9983399‘,
  19203 => ‘9984767‘,
  18970 => ‘9984776‘,
  12227 => ‘9984834‘,
  17479 => ‘9986766‘,
  19803 => ‘9986937‘,
  19509 => ‘9987704‘,
  11215 => ‘9988372‘,
  18280 => ‘9989817‘,
  10092 => ‘9990978‘,
  19089 => ‘9992132‘,
  11744 => ‘9992693‘,
  12533 => ‘9994185‘,
  14711 => ‘9994771‘,
  18623 => ‘9996266‘,
  16919 => ‘9997883‘,
  10886 => ‘9998931‘,
  11263 => ‘9999083‘,
)

源码请见：https://github.com/billfeller/generate-rank-with-redis-sorted-set