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CREATE TABLE tablename (`ID` INTEGER, `Username` VARCHAR(1), `RegistrationDatetime` DATETIME);
INSERT INTO tablename (`ID`, `Username`, `RegistrationDatetime`) VALUES
('1', 'A', '2022-01-03 12:00:00'),
('2', 'B', '2022-01-03 14:00:00'),
('3', 'C', '2022-01-04 23:00:00'),
('4', 'D', '2022-01-04 14:00:00'),
('5', 'E', '2022-01-05 14:00:00');
Records: 5 Duplicates: 0 Warnings: 0
SELECT DISTINCT
DATE(RegistrationDatetime) AS Date,
COUNT(*) OVER (ORDER BY DATE(RegistrationDatetime)) AS Count
FROM tablename;
| Date | Count |
|---|---|
| 2022-01-03 | 2 |
| 2022-01-04 | 4 |
| 2022-01-05 | 5 |