Multi-event tournament standings (with arbitrary number of entries) - mysql

Question

Suppose you have a a multi-event competition where competitors can attempt any event an arbitrary number of times. (weird, I know.)
How do pull out a desired player's best time for each event,
and assign it a placing? (1st 2nd 3rd...)
Data example: Desired output:
Name | Event | Score Name | Event | Score | Rank
-------------------- ----------------------------
Bob 1 50 Given input: "Bob"
Bob 1 100 Bob 1 100 1
Bob 2 75 Bob 2 75 3
Bob 3 80 Bob 3 80 2
Bob 3 65
Given input: "Jill"
Jill 2 75 Jill 2 90 1
Jill 2 90 Jill 3 60 3
Jill 3 60
Given input: "Chris"
Chris 1 70 Chris 1 70 2
Chris 2 50 Chris 2 85 2
Chris 2 85 Chris 3 100 1
Chris 3 100
This is a build up of my previous question:
Multi-event tournament standings
I feel understand that problem much better (Thanks!), but I cannot bridge the gap to this version of the problem.
I have SQL 5.x so I cant use stuff like Rank(). This will also be crunching many thousands of scores.

Answer 1

Desired output can be acheaved with this query:
select
IF(event is NULL, CONCAT('Given input: "', name,'"'), name) as name,
IF(event is NULL, '', event) as event,
IF(event is NULL, '', max(score)) as score,
IF(event is NULL, '', (
select count(s2.name) + 1
from (
select name, max(score) as score
from scores es
where es.event = s.event
group by es.name
order by score desc
) s2
where s2.score > max(s.score)
)) as `rank`
from scores s
group by name, event with rollup
having name is not NULL
order by name, event;
And output (if run query in mysql cli):
+----------------------+-------+-------+------+
| name | event | score | rank |
+----------------------+-------+-------+------+
| Given input: "Bob" | | | |
| Bob | 1 | 100 | 1 |
| Bob | 2 | 75 | 3 |
| Bob | 3 | 80 | 2 |
| Given input: "Chris" | | | |
| Chris | 1 | 70 | 2 |
| Chris | 2 | 85 | 2 |
| Chris | 3 | 100 | 1 |
| Given input: "Jill" | | | |
| Jill | 2 | 90 | 1 |
| Jill | 3 | 60 | 3 |
+----------------------+-------+-------+------+
11 rows in set, 3 warnings (0.00 sec)
Should work on any Mysql 5.

Answer 2

You can get the highest score per event by an aggregation by event taking the max(). To simulate a dense_rank() you can use a subquery counting the scores higher than or equal to the current score per event.
For a particular contestant (here Bob) that makes:
SELECT d1.name,
d1.event,
max(d1.score) score,
(SELECT count(*)
FROM (SELECT d2.event,
max(d2.score) score
FROM data d2
GROUP BY d2.event,
d2.name) x1
WHERE x1.score >= max(d1.score)
AND x1.event = d1.event) rank
FROM data d1
WHERE d1.name = 'Bob'
GROUP BY d1.event
ORDER BY d1.event;
And for all of them at once:
SELECT d1.name,
d1.event,
max(d1.score) score,
(SELECT count(*)
FROM (SELECT d2.event,
max(d2.score) score
FROM data d2
GROUP BY d2.event,
d2.name) x1
WHERE x1.score >= max(d1.score)
AND x1.event = d1.event) rank
FROM data d1
GROUP BY d1.name,
d1.event
ORDER BY d1.name,
d1.event;
db<>fiddle

Answer 3

E.g.:
DROP TABLE IF EXISTS my_table;
CREATE TABLE my_table
(id SERIAL PRIMARY KEY
,name VARCHAR(12) NOT NULL
,event INT NOT NULL
,score INT NOT NULL
);
INSERT INTO my_table (name,event,score) VALUES
('Bob' ,1, 50),
('Bob' ,1,100),
('Bob' ,2, 75),
('Bob' ,3, 80),
('Bob' ,3, 65),
('Jill' ,2, 75),
('Jill' ,2, 90),
('Jill' ,3, 60),
('Chris',1, 70),
('Chris',2, 50),
('Chris',2, 85),
('Chris',3,100);
SELECT a.*
, FIND_IN_SET(a.score,b.scores) my_rank
FROM my_table a -- it's possible that this really needs to be a repeat of the subquery below, so
-- ( SELECT m.* FROM my_table m JOIN (SELECT name,event,MAX(score) score FROM my_table
-- GROUP BY name, event) n ON n.name = m.name AND n.event = m.event AND n.score = m.score) AS a
JOIN
(
SELECT x.event
, GROUP_CONCAT(DISTINCT x.score ORDER BY x.score DESC) scores
FROM my_table x
JOIN
( SELECT name
, event
, MAX(score) score
FROM my_table
GROUP
BY name
, event
) y
ON y.name = x.name
AND y.event = x.event
AND y.score = x.score
GROUP
BY x.event
) b
ON b.event = a.event
WHERE FIND_IN_SET(a.score,b.scores) >0;
+----+-------+-------+-------+------+
| id | name | event | score | rank |
+----+-------+-------+-------+------+
| 2 | Bob | 1 | 100 | 1 |
| 3 | Bob | 2 | 75 | 3 |
| 4 | Bob | 3 | 80 | 2 |
| 6 | Jill | 2 | 75 | 3 |
| 7 | Jill | 2 | 90 | 1 |
| 8 | Jill | 3 | 60 | 3 |
| 9 | Chris | 1 | 70 | 2 |
| 11 | Chris | 2 | 85 | 2 |
| 12 | Chris | 3 | 100 | 1 |
+----+-------+-------+-------+------+