Untitled

-- MySQL 5.0

alter table task_log add column task_log_created datetime default '1900-01-01 00:00:00';

delimiter //

CREATE TRIGGER task_log_created_trigger BEFORE INSERT ON task_log
FOR EACH ROW
BEGIN
  IF NEW.task_log_created = "1900-01-01 00:00:00" THEN
    SET NEW.task_log_created = NOW();
  END IF;
END;//

delimiter ;

alter table task_log add column task_log_modified timestamp default current_timestamp on update current_timestamp;