Oracle 21c

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CREATE TABLE tab(
	ID		INT, 
	POS		INT,
	X		INT,
	Y		INT
);

INSERT ALL 
    INTO tab VALUES (1, 1, 11, 21)
    INTO tab VALUES (2, 1, 12, 22)
    INTO tab VALUES (3, 1, 13, 23)
    INTO tab VALUES (1, 3, 14, 24)
    INTO tab VALUES (1, 2, 15, 25)
    INTO tab VALUES (4, 1, 16, 26)
SELECT * FROM dual;
6 rows affected

SELECT ID,  
       LISTAGG('(' || X || ', ' || Y || ')', ', ') WITHIN GROUP (ORDER BY POS) AS XY
FROM tab
GROUP BY ID


ID
XY


1
(11, 21), (15, 25), (14, 24)

2
(12, 22)

3
(13, 23)

4
(16, 26)