MySQL 8.0

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SELECT VERSION();


VERSION()


8.0.30


DROP TABLE IF EXISTS `tbl_table`;

CREATE TABLE IF NOT EXISTS `tbl_table` (
  `json_field` JSON,
  `created_on` TIMESTAMP(6) GENERATED ALWAYS AS (`json_field` ->> '$.createdOn') VIRTUAL
);
INSERT INTO `tbl_table`
  (`json_field`)
VALUES
  ('{"createdOn": "2020-03-05T04:30:00.000+00:00"}');
SELECT
  `json_field`,
  `created_on`
FROM
  `tbl_table`;


json_field
created_on


7b22637265617465644f6e223a2022323032302d30332d30355430343a33303a30302e3030302b30303a3030227d
2020-03-05 04:30:00.000000


INSERT INTO `tbl_table`
  (`json_field`)
VALUES
  ('{"createdOn": "2020-03-05T04:30:00.000+0000"}');

Incorrect datetime value: '2020-03-05T04:30:00.000+0000' for column 'created_on' at row 1


SELECT
  `json_field`,
  `created_on`
FROM
  `tbl_table`;


json_field
created_on


7b22637265617465644f6e223a2022323032302d30332d30355430343a33303a30302e3030302b30303a3030227d
2020-03-05 04:30:00.000000