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CREATE TABLE table_a
(timestamp datetime)
;
INSERT INTO table_a
(timestamp)
VALUES
('2020-11-28 04:00:00'),
('2020-11-28 05:00:00'),
('2020-11-29 01:00:00'),
('2020-11-29 02:00:00'),
('2020-11-29 03:00:00')
;
SELECT CAST(DATE(timestamp) AS DATETIME) AS my_datetime,
COUNT(*) AS count
FROM table_a
GROUP BY my_datetime;
| my_datetime | count |
|---|---|
| 2020-11-28 00:00:00 | 2 |
| 2020-11-29 00:00:00 | 3 |