MariaDB 10.4

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CREATE TABLE organigram (
    idElement INT NOT NULL AUTO_INCREMENT,
    idClient  INT,
    idSubClient INT,
    idSport INT,
    idCategory INT,
    idTeam INT,
    idParent INT,
    PRIMARY KEY(idElement)
);
INSERT INTO organigram
    (idElement, idClient, idSubClient, idSport, idCategory, idTeam, idParent)
VALUES
    (1, 1, -1, NULL, NULL, NULL, NULL),
    (2, 1, -1, 30, NULL, NULL, 1),
    (3, 1, -1, NULL, 100, NULL, 2),
    (4, 1, -1, 31, NULL, NULL, 1),
    (5, 1, -1, NULL, NULL, 150, 3),
    (6, 1, -1, NULL, NULL, 151, 3),
    (7, 1, -1, NULL, 101, NULL, 4),
    (8, 1, -1, NULL, 101, NULL, 2),
    (9, 1, -1, NULL, NULL, 152, 7),
    (10, 1, -1, NULL, NULL, 153, 7)
;
CREATE TABLE organigram_users (
    idRef INT NOT NULL AUTO_INCREMENT,
    idElement  INT,
    idUser INT,
    PRIMARY KEY(idRef)
);
INSERT INTO organigram_users
    (idRef, idElement, idUser)
VALUES
    (1, 1, 2000),
    (2, 1, 2001),
    (3, 1, 2002),
    (4, 1, 2003),
    (5, 2, 2004),
    (6, 2, 2005),
    (7, 3, 2001),
    (8, 4, 2003),
    (9, 9, 2004);
with recursive
u as (
  select
    u.idUser, u.idElement as root, 
    o.idElement, o.idParent, o.idSport, 1 as lvl from organigram_users u
  join organigram o on o.idElement = u.idElement
  where u.idUser = 2004
 UNION ALL
  select u.idUser, u.root, o.idElement, o.idParent, o.idSport, u.lvl + 1
  from u 
  join organigram o on o.idElement = u.idParent and u.idSport is null
)
,
s as (
  select *
  from (
    select *,
      row_number() over(partition by idUser, root order by lvl desc) as rn
    from u 
  ) x
  where rn = 1
)
select * from s; -- idElement shows 2, 4


idUser
root
idElement
idParent
idSport
lvl
rn


2004
2
2
1
30
1
1

2004
9
4
1
31
3
1