MySQL MAX value with 2 conditions - mysql

Question

I'm trying to update SQL table with results of students contest. For that contest I've 2 tables: participants (name, class, school, etc.) and results (participant_id, results and subject). Now I need to give each participant a status - 1st place, 2nd place or 3d place based on their results.
The tricky part is the rules of that contest. Each participant must get this status in their respective school and class. So I must have winners in each school and each class. It's quite simple to update table with 2nd and 3d place as they counted as result >= 50 and result < 50. But the 1st place must be the highest score in this school and in this class.
I tried a lot of combinations with MAX() statement but with no success. No matter what I try I can't make it show maximum value based on 2 conditions (max in school, max in class). I need something like =MAXIFS() in Excel, but don't know how to do it in SQL.
UPD. Examples
Table participants
| id | name | class | school |
------------------------------
| 01 | John | 10 | 312 |
| 02 | Jack | 10 | 312 |
| 03 | Mary | 11 | 144 |
| 04 | Dany | 11 | 312 |
| 05 | Mark | 7 | 144 |
Table results
| id | participant_id | subject | score |
-----------------------------------------
| 01 | 03 | 4 | 55 |
| 02 | 01 | 4 | 75 |
| 03 | 04 | 4 | 60 |
| 04 | 05 | 4 | 45 |
| 05 | 02 | 4 | 90 |
And the result I need must look like this:
| id | participant_id | subject | score | status |
-----------------------------------------------------
| 01 | 03 | 4 | 55 | 1st place |
| 02 | 01 | 4 | 75 | 2nd place |
| 03 | 04 | 4 | 60 | 3rd place |
| 04 | 05 | 4 | 45 | 3rd place |
| 05 | 02 | 4 | 90 | 1st place |
Basically, 1st place is MAX in each school and class, 2nd is less than MAX and >= 50 and 3rd is just less than 50.
Can't show everything I tried because it's all variations of the same query. Something like that:
SELECT
id, participant_id, subject, score,
(CASE
WHEN score >= 50 THEN '2nd place'
WHEN score < 50 THEN '3rd place'
WHEN score = MAX(score) THEN '1st place'
END) AS 'status'
FROM results
INNER JOIN participants ON results.participant_id = participants.id
GROUP BY participant_id
I've also tried with subqueries, but it's obviously not helping - different subqueries even give different number of rows or resulting 'status' doesn't match the score and other information.

Answer 1

The next query can be used as solution:
SELECT
participants.*,
results.*,
(CASE
WHEN score = max_score THEN '1st place'
WHEN score >= 50 THEN '2nd place'
WHEN score < 50 THEN '3rd place'
END) AS 'status'
FROM participants
JOIN results ON results.participant_id = participants.id
JOIN (
SELECT
class, school, max(score) max_score
FROM results
INNER JOIN participants ON results.participant_id = participants.id
GROUP BY class, school
) max_results ON
max_results.class = participants.class AND
max_results.school = participants.school;
And here the fiddle: SQLize.online