
ALTER TABLE `omc_db`.`alarm_log` 
MODIFY COLUMN `log_time` datetime NOT NULL DEFAULT current_timestamp() AFTER `event_time`;

UPDATE `omc_db`.`alarm_log`
SET event_time = STR_TO_DATE(SUBSTRING_INDEX(CONVERT_TZ(SUBSTRING_INDEX(event_time, '+', 1), '+08:00', CONCAT('+', SUBSTRING_INDEX(event_time, '+', -1))), '.', 1), '%Y-%m-%d %H:%i:%s');

ALTER TABLE `omc_db`.`alarm_log` 
MODIFY COLUMN `event_time` datetime NULL DEFAULT NULL AFTER `alarm_status`;