MySQL 8.0

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CREATE TABLE table1 (
  `id` INTEGER,
  `user` INTEGER,
  `timestamp` DATETIME,
  `extra` INTEGER
);

INSERT INTO table1
  (`id`, `user`, `timestamp`, `extra`)
VALUES
  ('1', '1', '2021-05-18 15:46:18', '0'),
  ('2', '2', '2021-05-18 15:41:18', '0'),
  ('3', '2', '2021-05-18 15:38:18', '1'),
  ('4', '2', '2021-05-18 15:19:18', '0'),
  ('5', '2', '2021-05-18 15:12:18', '0'),
  ('6', '1', '2021-05-18 14:46:18', '0'),
  ('7', '2', '2021-05-18 14:46:18', '0'),
  ('8', '2', '2021-05-18 14:13:18', '0'),
  ('9', '1', '2021-05-18 12:58:18', '0'),
  ('10', '2', '2021-05-18 12:46:18', '0'),
  ('11', '1', '2021-05-18 12:13:18', '0'),
  ('12', '1', '2021-05-18 12:01:18', '0');
UPDATE table1 t1
JOIN (SELECT
`id`,
IF(ROW_NUMBER() OVER( PARTITION BY `user`,DATE_FORMAT(`timestamp`,'%Y-%m-%d %h') ORDER BY `user`,`timestamp`) < 3,0,1) extra
FROM table1) t2 ON t1.id = t2.id
SET t1.`extra` = t2.`extra`
SELECT * FROM table1


id
user
timestamp
extra


1
1
2021-05-18 15:46:18
0

2
2
2021-05-18 15:41:18
1

3
2
2021-05-18 15:38:18
1

4
2
2021-05-18 15:19:18
0

5
2
2021-05-18 15:12:18
0

6
1
2021-05-18 14:46:18
0

7
2
2021-05-18 14:46:18
0

8
2
2021-05-18 14:13:18
0

9
1
2021-05-18 12:58:18
1

10
2
2021-05-18 12:46:18
0

11
1
2021-05-18 12:13:18
0

12
1
2021-05-18 12:01:18
0

id	user	timestamp	extra
1	1	2021-05-18 15:46:18	0
2	2	2021-05-18 15:41:18	1
3	2	2021-05-18 15:38:18	1
4	2	2021-05-18 15:19:18	0
5	2	2021-05-18 15:12:18	0
6	1	2021-05-18 14:46:18	0
7	2	2021-05-18 14:46:18	0
8	2	2021-05-18 14:13:18	0
9	1	2021-05-18 12:58:18	1
10	2	2021-05-18 12:46:18	0
11	1	2021-05-18 12:13:18	0
12	1	2021-05-18 12:01:18	0