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CREATE TABLE coin_history (
id SERIAL PRIMARY KEY,
coin_id INT NOT NULL,
exchange_rate FLOAT NOT NULL,
timestamp TIMESTAMP
);
CREATE TABLE
INSERT INTO coin_history(coin_id, exchange_rate, timestamp)
VALUES
(1, 1.3, '2007-01-01 00:00:00'),
(1, 2.3, '2007-01-02 00:00:00'),
(1, 3.3, '2007-01-12 00:00:00'),
(1, 4.3, '2007-02-01 00:00:00'),
(1, 5.3, '2007-02-12 00:00:00'),
(2, 1.3, '2007-01-01 00:00:00'),
(2, 2.3, '2007-01-12 00:00:00'),
(2, 3.3, '2007-02-01 00:00:00'),
(2, 4.3, '2007-02-12 00:00:00'),
(3, 1.3, '2007-01-01 00:00:00'),
(3, 2.3, '2007-01-12 00:00:00'),
(3, 3.3, '2007-02-01 00:00:00'),
(3, 4.3, '2007-02-12 00:00:00'),
(3, 5.3, '2008-01-01 00:00:00'),
(3, 6.3, '2008-01-12 00:00:00');
INSERT 0 15
SELECT
id,
coin_id,
AVG(exchange_rate) OVER (PARTITION BY coin_id, DATE_TRUNC('WEEK', timestamp)) AS by_week,
AVG(exchange_rate) OVER (PARTITION BY coin_id, DATE_TRUNC('MONTH', timestamp)) AS by_month,
AVG(exchange_rate) OVER (PARTITION BY coin_id, DATE_TRUNC('YEAR', timestamp)) AS by_year
FROM coin_history
ORDER BY id
| id | coin_id | by_week | by_month | by_year |
|---|---|---|---|---|
| 1 | 1 | 1.7999999999999998 | 2.3 | 3.3 |
| 2 | 1 | 1.7999999999999998 | 2.3 | 3.3 |
| 3 | 1 | 3.3 | 2.3 | 3.3 |
| 4 | 1 | 4.3 | 4.8 | 3.3 |
| 5 | 1 | 5.3 | 4.8 | 3.3 |
| 6 | 2 | 1.3 | 1.7999999999999998 | 2.8 |
| 7 | 2 | 2.3 | 1.7999999999999998 | 2.8 |
| 8 | 2 | 3.3 | 3.8 | 2.8 |
| 9 | 2 | 4.3 | 3.8 | 2.8 |
| 10 | 3 | 1.3 | 1.7999999999999998 | 2.8 |
| 11 | 3 | 2.3 | 1.7999999999999998 | 2.8 |
| 12 | 3 | 3.3 | 3.8 | 2.8 |
| 13 | 3 | 4.3 | 3.8 | 2.8 |
| 14 | 3 | 5.3 | 5.8 | 5.8 |
| 15 | 3 | 6.3 | 5.8 | 5.8 |
SELECT 15