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CREATE TABLE T(
no int,
flt_id int,
flight varchar(50),
flightDate datetime
);
INSERT INTO T VALUES (1,154024,'3K0722','2019-01-08 17:10:00.000');
INSERT INTO T VALUES (2,154024,'3K0722','2019-01-08 20:20:00.000');
INSERT INTO T VALUES (3,154024,'3K0723','2019-01-09 17:10:00.000');
INSERT INTO T VALUES (4,154024,'3K0724','2019-01-10 20:20:00.000');
SELECT (CASE WHEN rn = 1 THEN DENSE_RANK() over(order by flight) END) no,
(CASE WHEN rn = 1 THEN flt_id END) flt_id,
(CASE WHEN rn = 1 THEN flight END) flight,
flightDate
FROM
(
SELECT *,ROW_NUMBER() OVER(PARTITION BY flt_id,flight ORDER BY flightDate) rn
FROM T
) t1
| no | flt_id | flight | flightDate |
|---|---|---|---|
| 1 | 154024 | 3K0722 | 2019-01-08 17:10:00.000 |
| null | null | null | 2019-01-08 20:20:00.000 |
| 2 | 154024 | 3K0723 | 2019-01-09 17:10:00.000 |
| 3 | 154024 | 3K0724 | 2019-01-10 20:20:00.000 |