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CREATE TABLE table1 (
`id` INTEGER,
`date` Date,
`product` VARCHAR(1)
);
INSERT INTO table1
(`id`, `date`, `product`)
VALUES
('1', '2010-02-01', 'c'),
('1', '2010-02-02', 'v'),
('1', '2010-02-03', 'd'),
('1', '2010-02-04', 'g'),
('2', '2010-02-03', 'h'),
('2', '2010-02-04', 'w'),
('2', '2010-02-05', 't'),
('2', '2010-02-06', 'd'),
('3', '2010-02-04', 'x'),
('3', '2010-02-05', 'f'),
('3', '2010-02-06', 'x');
SELECT `id`, `date`, `product`
, FIRST_VALUE(`product`) OVER(PARTITION BY `id` ORDER BY `date` ROWS UNBOUNDED PRECEDING) minproduct
FROM table1
| id | date | product | minproduct |
|---|---|---|---|
| 1 | 2010-02-01 | c | c |
| 1 | 2010-02-02 | v | c |
| 1 | 2010-02-03 | d | c |
| 1 | 2010-02-04 | g | c |
| 2 | 2010-02-03 | h | h |
| 2 | 2010-02-04 | w | h |
| 2 | 2010-02-05 | t | h |
| 2 | 2010-02-06 | d | h |
| 3 | 2010-02-04 | x | x |
| 3 | 2010-02-05 | f | x |
| 3 | 2010-02-06 | x | x |