MySQL 8.0

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CREATE TABLE userslive (userid INT, timer INT);
INSERT INTO userslive VALUES 
(1,1),
(2,2),
(3,3),
(4,4),
(5,5),
(2,6),
(4,7),
(2,8),
(6,9);
SELECT * FROM userslive ORDER BY userid, timer;


userid
timer


1
1

2
2

2
6

2
8

3
3

4
4

4
7

5
5

6
9


DELETE t1.*
FROM userslive t1, userslive t2
WHERE t1.userid = t2.userid  
  AND t1.timer < t2.timer;
SELECT * FROM userslive ORDER BY userid, timer;


userid
timer


1
1

2
8

3
3

4
7

5
5

6
9