[SQL]LeetCode178. 分数排名 | Rank Scores

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Write a SQL query to rank scores. If there is a tie between two scores, both should have the same ranking. Note that after a tie, the next ranking number should be the next consecutive integer value. In other words, there should be no "holes" between ranks.

+----+-------+
| Id | Score |
+----+-------+
| 1  | 3.50  |
| 2  | 3.65  |
| 3  | 4.00  |
| 4  | 3.85  |
| 5  | 4.00  |
| 6  | 3.65  |
+----+-------+

For example, given the above Scores table, your query should generate the following report (order by highest score):

+-------+------+
| Score | Rank |
+-------+------+
| 4.00  | 1    |
| 4.00  | 1    |
| 3.85  | 2    |
| 3.65  | 3    |
| 3.65  | 3    |
| 3.50  | 4    |
+-------+------+

---

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    |
+-------+------+

---

137ms

# Write your MySQL query statement below
Select Score,
@rank:=@rank + (@pre<>(@pre:=Score)) as Rank
From Scores, (Select @rank:=0, @pre:=-1) INIT
Order by Score DESC;

---

139ms

# Write your MySQL query statement below

select f.score Score, f.Rank from
(select 
@rnk:=@rnk + case when @score > s.score then 1 else 0 end as Rank
,@score:= s.score as score
from 
(select score from scores order by score desc) s,(select @score:=0,@rnk:=1) t) f

---

142ms

# Write your MySQL query statement below
Select Score,
@rank:=@rank + (@pre<>(@pre:=Score)) as Rank
From Scores, (Select @rank:=0, @pre:=-2) INIT
Order by Score DESC;

---

143ms

# Write your MySQL query statement below
SELECT
  Score,
  @rank := @rank + (@prev <> (@prev := Score)) Rank
FROM
  Scores,
  (SELECT @rank := 0, @prev := -1) init
ORDER BY Score desc

---

146ms

# Write your MySQL query statement below
select Score, CONVERT(Rank, SIGNED) AS Rank from (
select Score,
if(Score = @previous_score, @rank := @rank, @rank := @rank +1) as Rank,
@previous_score := score
from Scores, (select @rank := 0, @previous_score:= null) r
order by Score desc)v

---

552ms

# Write your MySQL query statement below

SELECT s.Score, count(distinct t.score) Rank
FROM Scores s JOIN Scores t ON s.Score <= t.score
GROUP BY s.Id
ORDER BY s.Score desc

---

553ms

# Write your MySQL query statement below
SELECT s1.Score, count(distinct s2.Score) as Rank
FROM Scores s1 
    join Scores s2 on s1.Score <= S2.Score
GROUP BY s1.Id
ORDER BY 2