MySQL 8.0

By using db<>fiddle, you agree to license everything you submit by Creative Commons CC0.

CREATE TABLE activity (
  `player_id` INTEGER,
  `device_id` INTEGER,
  `event_date` VARCHAR(10),
  `games_played` INTEGER
);

INSERT INTO activity
  (`player_id`, `device_id`, `event_date`, `games_played`)
VALUES
  ('1', '2', '2016-03-01', '5'),
  ('1', '2', '2016-05-02', '6'),
  ('1', '3', '2017-06-25', '1'),
  ('3', '1', '2016-03-02', '0'),
  ('3', '4', '2018-07-03', '5');
select a1.player_id, a1.event_date,a2.player_id, a2.event_date
from activity as a1
inner join activity as a2
on a1.event_date >= a2.event_date
and a1.player_id = a2.player_id


player_id
event_date
player_id
event_date


1
2017-06-25
1
2016-03-01

1
2016-05-02
1
2016-03-01

1
2016-03-01
1
2016-03-01

1
2017-06-25
1
2016-05-02

1
2016-05-02
1
2016-05-02

1
2017-06-25
1
2017-06-25

3
2018-07-03
3
2016-03-02

3
2016-03-02
3
2016-03-02

3
2018-07-03
3
2018-07-03


select a1.player_id, a1.event_date, sum(a2.games_played) as games_played_so_far
from activity as a1
inner join activity as a2
on a1.event_date >= a2.event_date
and a1.player_id = a2.player_id
group by  a1.player_id, a1.event_date
ORDER BY a1.player_id, a1.event_date


player_id
event_date
games_played_so_far


1
2016-03-01
5

1
2016-05-02
11

1
2017-06-25
12

3
2016-03-02
0

3
2018-07-03
5

player_id	event_date	player_id	event_date
1	2017-06-25	1	2016-03-01
1	2016-05-02	1	2016-03-01
1	2016-03-01	1	2016-03-01
1	2017-06-25	1	2016-05-02
1	2016-05-02	1	2016-05-02
1	2017-06-25	1	2017-06-25
3	2018-07-03	3	2016-03-02
3	2016-03-02	3	2016-03-02
3	2018-07-03	3	2018-07-03