Oracle 18c

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CREATE TABLE tba (id, map) AS
SELECT 1, CAST(NULL AS VARCHAR2(5)) FROM DUAL UNION ALL
SELECT 1, CAST(NULL AS VARCHAR2(5)) FROM DUAL UNION ALL
SELECT 2, CAST(NULL AS VARCHAR2(5)) FROM DUAL UNION ALL
SELECT 2, CAST(NULL AS VARCHAR2(5)) FROM DUAL UNION ALL
SELECT 2, CAST(NULL AS VARCHAR2(5)) FROM DUAL UNION ALL
SELECT 3, CAST(NULL AS VARCHAR2(5)) FROM DUAL UNION ALL
SELECT 3, CAST(NULL AS VARCHAR2(5)) FROM DUAL UNION ALL
SELECT 4, CAST(NULL AS VARCHAR2(5)) FROM DUAL;
8 rows affected

CREATE TABLE tbb (id, map) AS
SELECT 1, CAST(NULL AS VARCHAR2(5)) FROM DUAL UNION ALL
SELECT 1, CAST(NULL AS VARCHAR2(5)) FROM DUAL UNION ALL
SELECT 1, CAST(NULL AS VARCHAR2(5)) FROM DUAL UNION ALL
SELECT 2, CAST(NULL AS VARCHAR2(5)) FROM DUAL UNION ALL
SELECT 3, CAST(NULL AS VARCHAR2(5)) FROM DUAL UNION ALL
SELECT 3, CAST(NULL AS VARCHAR2(5)) FROM DUAL UNION ALL
SELECT 4, CAST(NULL AS VARCHAR2(5)) FROM DUAL UNION ALL
SELECT 4, CAST(NULL AS VARCHAR2(5)) FROM DUAL;
8 rows affected

UPDATE tba
SET map = 'ok'
WHERE ROWID IN (
  SELECT a.rid
  FROM   (
           SELECT ROWID AS rid,
                  id,
                  ROW_NUMBER() OVER (PARTITION BY id ORDER BY ROWNUM) AS rn
           FROM   tba
         ) a
         INNER JOIN (
           SELECT id,
                  ROW_NUMBER() OVER (PARTITION BY id ORDER BY ROWNUM) AS rn
           FROM   tbb
         ) b
         ON a.id = b.id AND a.rn = b.rn
);
6 rows affected

UPDATE tbb
SET map = 'ok'
WHERE ROWID IN (
  SELECT b.rid
  FROM   (
           SELECT ROWID AS rid,
                  id,
                  ROW_NUMBER() OVER (PARTITION BY id ORDER BY ROWNUM) AS rn
           FROM   tbb
         ) b
         INNER JOIN (
           SELECT id,
                  ROW_NUMBER() OVER (PARTITION BY id ORDER BY ROWNUM) AS rn
           FROM   tba
         ) a
         ON a.id = b.id AND a.rn = b.rn
);
6 rows affected

SELECT * FROM tba;


ID
MAP


1
ok

1
ok

2
ok

2
null

2
null

3
ok

3
ok

4
ok


SELECT * FROM tbb;


ID
MAP


1
ok

1
ok

1
null

2
ok

3
ok

3
ok

4
ok

4
null
ID	MAP
1	ok
1	ok
2	ok
2	null
2	null
3	ok
3	ok
4	ok
ID	MAP
1	ok
1	ok
1	null
2	ok
3	ok
3	ok
4	ok
4	null