Firebird 3.0

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CREATE TABLE Tab(
ID INTEGER
, DT TIMESTAMP
, NUMBER INTEGER
, V NUMERIC(18,2)
);


EXECUTE BLOCK
AS
BEGIN
INSERT INTO TAB(ID, DT, NUMBER, V) VALUES(1, '2021-03-14 14:00', 1, 11.1);
INSERT INTO TAB(ID, DT, NUMBER, V) VALUES(2, '2021-03-14 14:00', 2, 11.2);
INSERT INTO TAB(ID, DT, NUMBER, V) VALUES(3, '2021-03-14 14:00', 3, 11.3);
INSERT INTO TAB(ID, DT, NUMBER, V) VALUES(4, '2021-03-14 14:01', 1, 12.1);
INSERT INTO TAB(ID, DT, NUMBER, V) VALUES(5, '2021-03-14 14:01', 2, 12.2);
INSERT INTO TAB(ID, DT, NUMBER, V) VALUES(6, '2021-03-14 14:01', 3, 12.3);
INSERT INTO TAB(ID, DT, NUMBER, V) VALUES(7, '2021-03-14 14:02', 1, 13.1);
INSERT INTO TAB(ID, DT, NUMBER, V) VALUES(8, '2021-03-14 14:02', 2, 13.2);
INSERT INTO TAB(ID, DT, NUMBER, V) VALUES(9, '2021-03-14 14:02', 3, 13.3);
INSERT INTO TAB(ID, DT, NUMBER, V) VALUES(10, '2021-03-14 14:03', 1, 14.1);
INSERT INTO TAB(ID, DT, NUMBER, V) VALUES(11, '2021-03-14 14:04', 2, 14.2);
INSERT INTO TAB(ID, DT, NUMBER, V) VALUES(12, '2021-03-14 14:04', 3, 14.3);
END
12 rows affected

SELECT
T.DT
, MIN(CASE WHEN T.NUMBER=1 THEN T.V ELSE NULL END) AS "1"
, MIN(CASE WHEN T.NUMBER=2 THEN T.V ELSE NULL END) AS "2"
, MIN(CASE WHEN T.NUMBER=3 THEN T.V ELSE NULL END) AS "3"
FROM
TAB T
GROUP BY T.DT


DT
1
2
3


2021-03-14 14:00:00
11.10
11.20
11.30

2021-03-14 14:01:00
12.10
12.20
12.30

2021-03-14 14:02:00
13.10
13.20
13.30

2021-03-14 14:03:00
14.10
null
null

2021-03-14 14:04:00
null
14.20
14.30

DT	1	2	3
2021-03-14 14:00:00	11.10	11.20	11.30
2021-03-14 14:01:00	12.10	12.20	12.30
2021-03-14 14:02:00	13.10	13.20	13.30
2021-03-14 14:03:00	14.10	null	null
2021-03-14 14:04:00	null	14.20	14.30