Oracle 21c

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CREATE TABLE Employee(Id, NAME, Qualification, Experience) AS
SELECT 1, 'Aaron', 'Eng',  2 FROM DUAL UNION ALL
SELECT 2, 'Jacob', 'CS',   3 FROM DUAL UNION ALL
SELECT 3, 'Jehan', 'Art',  1 FROM DUAL UNION ALL
SELECT 4, 'Jenny', 'Math', 7 FROM DUAL;
4 rows affected

CREATE TABLE Task (Task_Name, Emp_id, duration, Wage) AS
SELECT 'clean',   '1,3',   200,  50 FROM DUAL UNION ALL
SELECT 'wash',    '4',     300, 200 FROM DUAL UNION ALL
SELECT 'decor',   '1,2,4', 250, 300 FROM DUAL UNION ALL
SELECT 'errands', '2,4',   150, 150 FROM DUAL;
4 rows affected

SELECT task_name,
       ( SELECT LISTAGG(e.name, ',') WITHIN GROUP (
                  ORDER BY INSTR(',' || t.emp_id || ',', ',' || e.id || ',')
                )
         FROM   Employee e
         WHERE  INSTR(',' || t.emp_id || ',', ',' || e.id || ',') > 0
       ) AS emp_names,
       duration,
       wage
FROM   task t


TASK_NAME
EMP_NAMES
DURATION
WAGE


clean
Aaron,Jehan
200
50

wash
Jenny
300
200

decor
Aaron,Jacob,Jenny
250
300

errands
Jacob,Jenny
150
150

TASK_NAME	EMP_NAMES	DURATION	WAGE
clean	Aaron,Jehan	200	50
wash	Jenny	300	200
decor	Aaron,Jacob,Jenny	250	300
errands	Jacob,Jenny	150	150