Oracle 18c

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CREATE TABLE Schedule(ID INT,Position VARCHAR2(10))
INSERT INTO Schedule
SELECT 1,'Tester' FROM dual UNION ALL
SELECT 2,'Tester' FROM dual UNION ALL
SELECT 3,'xyz'    FROM dual UNION ALL
SELECT 4,'Tester' FROM dual
4 rows affected

UPDATE Schedule
   SET Position = 'Manager'
 WHERE Position IN
       (SELECT Position
          FROM Schedule
         WHERE Position = 'Tester' 
         FETCH NEXT 1 ROW ONLY)
3 rows affected

SELECT * FROM Schedule


ID
POSITION


1
Manager

2
Manager

3
xyz

4
Manager


DELETE Schedule
4 rows affected

INSERT INTO Schedule
SELECT 1,'Tester' FROM dual UNION ALL
SELECT 2,'Tester' FROM dual UNION ALL
SELECT 3,'xyz'    FROM dual UNION ALL
SELECT 4,'Tester' FROM dual
4 rows affected

UPDATE Schedule
   SET Position = 'Manager'
 WHERE ID IN
       (SELECT ID
          FROM Schedule
         WHERE Position = 'Tester'
         FETCH NEXT 1 ROW ONLY)
1 rows affected

SELECT * FROM Schedule


ID
POSITION


1
Manager

2
Tester

3
xyz

4
Tester


DELETE Schedule
4 rows affected

INSERT INTO Schedule
SELECT 1,'Tester' FROM dual UNION ALL
SELECT 2,'Tester' FROM dual UNION ALL
SELECT 3,'xyz'    FROM dual UNION ALL
SELECT 4,'Tester' FROM dual
4 rows affected

UPDATE Schedule
   SET Position = 'Manager'
 WHERE ID IN
       (SELECT ID
          FROM Schedule
         WHERE Position = 'Tester'
         ORDER BY ID DESC
         FETCH FIRST 2 ROWS ONLY)
2 rows affected

SELECT * FROM Schedule


ID
POSITION


1
Tester

2
Manager

3
xyz

4
Manager