leetcode_178_分数排名

leetcode 178 分数排名

• 题目

  编写一个 SQL 查询来实现分数排名。
  
  如果两个分数相同，则两个分数排名（Rank）相同。请注意，平分后的下一个名次应该是下一个连续的整数值。换句话说，名次之间不应该有“间隔”。
  
  +----+-------+
  | Id | Score |
  +----+-------+
  | 1  | 3.50  |
  | 2  | 3.65  |
  | 3  | 4.00  |
  | 4  | 3.85  |
  | 5  | 4.00  |
  | 6  | 3.65  |
  +----+-------+
  例如，根据上述给定的 Scores 表，你的查询应该返回（按分数从高到低排列）：
  
  +-------+------+
  | Score | Rank |
  +-------+------+
  | 4.00  | 1    |
  | 4.00  | 1    |
  | 3.85  | 2    |
  | 3.65  | 3    |
  | 3.65  | 3    |
  | 3.50  | 4    |
  +-------+------+
  

• 解
  1. 暴力求解，计算表内比当前值大的去重个数为排名

     select s1.Score as Score,
     (select count(distinct s2.Score) from Scores as s2 where s2.Score>=s1.Score) as 'Rank'
     from Scores as s1
     order by s1.Score desc;