MySQL 8.0

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CREATE TABLE tablename(id int, regid int, docid int, archived int);

INSERT INTO tablename VALUES
   (1,1000,1,0), (2,1000,2,0), (3,1000,3,0),
   (4,2000,1,0), (5,2000,2,0),
   (6,3000,1,0), (7,3000,2,0), (8,3000,3,0),
   (9,3000,4,0);

Records: 9  Duplicates: 0  Warnings: 0


UPDATE tablename t1
INNER JOIN tablename t2
ON t2.regid = t1.regid AND t2.docid > t1.docid 
SET t1.archived = 1;

Rows matched: 6  Changed: 6  Warnings: 0


SELECT * FROM tablename;


id
regid
docid
archived


1
1000
1
1

2
1000
2
1

3
1000
3
0

4
2000
1
1

5
2000
2
0

6
3000
1
1

7
3000
2
1

8
3000
3
1

9
3000
4
0

id	regid	docid	archived
1	1000	1	1
2	1000	2	1
3	1000	3	0
4	2000	1	1
5	2000	2	0
6	3000	1	1
7	3000	2	1
8	3000	3	1
9	3000	4	0