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CREATE TABLE myTable (
coworker INTEGER,
date datetime
);
INSERT INTO myTable
(coworker, date)
VALUES
('1', '2020.10.30'),
('1', '2019.09.12'),
('1', '2018.05.29'),
('2', '2019.08.07'),
('3', '2020.03.12'),
('3', '2018.06.24'),
('4', '2020.08.16');
7 rows affected
select
coworker,
date
from
(
select
*,
row_number() over (partition by coworker order by date) as rn,
count(*) over (partition by coworker) as ttl
from myTable
) subq
where (ttl > 1 and rn = ttl - 1) or (ttl = 1 and rn = 1)
| coworker | date |
|---|---|
| 1 | 2019-09-12 00:00:00.000 |
| 2 | 2019-08-07 00:00:00.000 |
| 3 | 2018-06-24 00:00:00.000 |
| 4 | 2020-08-16 00:00:00.000 |