Description
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 |
+-------+------+
Solutions
1. Count
CREATE FUNCTION getNthHighestSalary(N INT) RETURNS INT
BEGIN
DECLARE M INT DEFAULT N-1;
-- DECLARE M INT;
-- SET M=N-1;
RETURN (
# Write your MySQL query statement below.
SELECT ( SELECT DISTINCT Salary
FROM Employee
ORDER by Salary DESC
-- LIMIT 1 offset M
LIMIT M, 1
)
);
END
-- 14/14 cases passed (184 ms)
-- Your runtime beats 97.82 % of mysql submissions
-- Your memory usage beats 100 % of mysql submissions (0B)
2. Two Variables
SELECT
Score,
@rank := @rank + (@prev <> (@prev := Score)) Rank
FROM
Scores,
(SELECT @rank := 0, @prev := -1) init
ORDER BY Score DESC
-- 10/10 cases passed (271 ms)
-- Your runtime beats 96.58 % of mysql submissions
-- Your memory usage beats 100 % of mysql submissions (0B)