需求：按照用户的积分对用户进行排名。
事例表结构
CREATE TABLE `users_points` ( `id` int(11) unsigned NOT NULL AUTO_INCREMENT, `user_id` bigint(20) NOT NULL COMMENT '用户ID', `score` int(11) NOT NULL COMMENT '分数', `score_rank` int(11) NOT NULL COMMENT '分数排名', `created_at` datetime NOT NULL COMMENT '创建时间', PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;依据score字段，对user_id进行排名，MySQL可以使用一条SQL实现
select a.user_id, a.score, (select count(distinct b.score) from users_points b where b.score >= a.score) as rank from users_points a order by score desc; 得出的结果 +----+-------+------+ | user_id | score | rank | +----+-------+------+ | 11 | 100 | 1 | | 8 | 80 | 2 | | 4 | 50 | 3 | | 12 | 45 | 4 | | 2 | 40 | 5 | | 6 | 30 | 6 | | 1 | 20 | 7 | | 10 | 15 | 8 | | 7 | 10 | 9 | | 5 | 10 | 9 | | 3 | 10 | 9 | | 9 | 5 | 10 | +----+-------+------+