ALTER TABLE `event_email_schedule` DROP INDEX `event_schedule_id`;
ALTER TABLE `event_email_schedule` CHANGE `event_schedule_id` `event_schedule_id` INT(10) NULL DEFAULT NULL COMMENT 'Could be event_schedule_id or event_id';


ALTER TABLE `event_email_recipient` DROP INDEX `event_schedule_id`;
ALTER TABLE `event_email_recipient` CHANGE `event_schedule_id` `event_schedule_id` INT(10) NULL DEFAULT NULL COMMENT 'Could be event_schedule_id or event_id';