SQL Coding Exercise – Rank Scores

Submit your SQL to Leetcode online judge: https://oj.leetcode.com/problems/rank-scores/

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

The following SQL returns the distinct scores:

Select Distinct Score from Scores

Then we can count how many and compute the rank:

Select Count(1) + 1 From (Select Distinct Score from Scores) as uniqeScores where Score > sc.Score

And put it in the entire SQL:

Select sc.Score,
       (Select Count(1) + 1 From (Select Distinct Score from Scores) as uniqeScores where Score > sc.Score) as rank 
From Scores sc 
Order by sc.Score Desc;

This gives a pretty good accepted results:

sql-rank-scores

–EOF (The Ultimate Computing & Technology Blog) —