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CREATE TABLE `test` (
`id` mediumint NOT NULL AUTO_INCREMENT,
`Date_VARCHAR` varchar(30) DEFAULT NULL,
`Date_TIMESTAMP` timestamp(6) NULL DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=52383 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;
INSERT INTO test (`Date_VARCHAR`)
VALUES('2021-05-10T08-45-30'), ('2021-05-10T08-46-30'), ('2021-05-10T08-47-30'), ('2021-05-10T08-48-30');
SELECT * FROM test;
Records: 4 Duplicates: 0 Warnings: 0
| id | Date_VARCHAR | Date_TIMESTAMP |
|---|---|---|
| 52383 | 2021-05-10T08-45-30 | null |
| 52384 | 2021-05-10T08-46-30 | null |
| 52385 | 2021-05-10T08-47-30 | null |
| 52386 | 2021-05-10T08-48-30 | null |
ALTER TABLE test
DROP COLUMN Date_TIMESTAMP,
ADD COLUMN Date_TIMESTAMP TIMESTAMP AS (STR_TO_DATE(Date_VARCHAR, '%Y-%m-%dT%h-%i-%s'));
Records: 0 Duplicates: 0 Warnings: 0
SELECT * FROM test;
| id | Date_VARCHAR | Date_TIMESTAMP |
|---|---|---|
| 52383 | 2021-05-10T08-45-30 | 2021-05-10 08:45:30 |
| 52384 | 2021-05-10T08-46-30 | 2021-05-10 08:46:30 |
| 52385 | 2021-05-10T08-47-30 | 2021-05-10 08:47:30 |
| 52386 | 2021-05-10T08-48-30 | 2021-05-10 08:48:30 |