Recursive CTE to traverse a hierarchy with dual descendant IDs - mysql

Question

Given the following table of sports matches with two players:
match_id
match_date
p1_id
p2_id
1
01/01/2022
1
2
2
02/01/2022
3
1
3
03/01/2022
3
4
4
04/01/2022
2
3
5
05/01/2022
5
6
6
06/01/2022
1
2
7
07/01/2022
3
1
8
08/01/2022
3
4
9
09/01/2022
2
3
10
10/01/2022
5
6
11
11/01/2022
3
4
12
12/01/2022
7
8
13
13/01/2022
3
1
14
14/01/2022
5
7
15
15/01/2022
4
5
I’m trying to write a query with a recursive CTE that when given a match_id the query will return all match_id values for future matches for each of the two players. The recursion is needed because I need the query to also include all future matches for any of the future matches' players.
Using the example above and match_id = 6 then the two player IDs are 1 and 2. I need the query to return all future matches for these player IDs. This means the query needs to return 7, 9 and 13. However, in match_id = 7 player ID 1 plays player ID 3 so now all of their future match_id values from that point also need to be included. This means the query also needs to return 8 and 11. In match_id = 8 and match_id = 11 player ID 3 plays player ID 4 so the final match_id to be returned is 15.
The expected output is as follows:
match_id
7
8
9
11
13
15
I've written the following query:
WITH RECURSIVE match_ids AS (
SELECT
m1.match_id,
m1.match_date,
m1.p1_id,
m1.p2_id
FROM recursive_test AS m1
WHERE m1.match_id = 6
UNION ALL
SELECT
m2.match_id,
m2.match_date,
m2.p1_id,
m2.p2_id
FROM recursive_test AS m2
INNER JOIN match_ids
ON (
match_ids.p1_id = m2.p1_id
OR match_ids.p1_id = m2.p2_id
OR match_ids.p2_id = m2.p1_id
OR match_ids.p2_id = m2.p2_id
)
AND match_ids.match_date > m2.match_date
)
SELECT match_id
FROM match_ids
However, this returns:
match_id
6
2
4
1
1
2
3
1
2
1
Where might I be going wrong?
Here's the SQL to create the table:
CREATE TABLE `recursive_test` (
`match_id` int NOT NULL,
`match_date` date NOT NULL,
`p1_id` int NOT NULL,
`p2_id` int NOT NULL,
PRIMARY KEY (`match_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;
INSERT INTO `recursive_test` VALUES (1,'2022-01-01',1,2),(2,'2022-01-02',3,1),(3,'2022-01-03',3,4),(4,'2022-01-04',2,3),(5,'2022-01-05',5,6),(6,'2022-01-06',1,2),(7,'2022-01-07',3,1),(8,'2022-01-08',3,4),(9,'2022-01-09',2,3),(10,'2022-01-10',5,6),(11,'2022-01-11',3,4),(12,'2022-01-12',7,8),(13,'2022-01-13',3,1),(14,'2022-01-14',5,7),(15,'2022-01-15',4,5);

Answer 1

WITH RECURSIVE
cte AS (
SELECT *
FROM recursive_test
WHERE match_id = #starting_match_id
UNION ALL
SELECT recursive_test.*
FROM recursive_test
JOIN cte ON recursive_test.match_date > cte.match_date
WHERE recursive_test.p1_id IN (cte.p1_id, cte.p2_id)
OR recursive_test.p2_id IN (cte.p1_id, cte.p2_id)
)
SELECT DISTINCT *
FROM cte;
https://dbfiddle.uk/?rdbms=mysql_8.0&fiddle=6ca1e57845bae995bacb04455beb6340