MySQL error when update foreign key - mysql

Question

I have 2 tables following below:
CREATE TABLE `queststatus` (
`queststatusid` int(10) unsigned NOT NULL AUTO_INCREMENT,
`characterid` int(11) NOT NULL DEFAULT '0',
`quest` int(6) NOT NULL DEFAULT '0',
`status` tinyint(4) NOT NULL DEFAULT '0',
`time` int(11) NOT NULL DEFAULT '0',
`forfeited` int(11) NOT NULL DEFAULT '0',
`customData` varchar(255) DEFAULT NULL,
PRIMARY KEY (`queststatusid`),
KEY `characterid` (`characterid`),
CONSTRAINT `queststatus_ibfk_1` FOREIGN KEY (`characterid`) REFERENCES `characters` (`id`) ON DELETE CASCADE ON UPDATE CASCADE
) ENGINE=InnoDB AUTO_INCREMENT=2148654268 DEFAULT CHARSET=utf8 ROW_FORMAT=FIXED
and
CREATE TABLE `queststatusmobs` (
`queststatusmobid` int(10) unsigned NOT NULL AUTO_INCREMENT,
`queststatusid` int(10) unsigned NOT NULL DEFAULT '0',
`mob` int(11) NOT NULL DEFAULT '0',
`count` int(11) NOT NULL DEFAULT '0',
PRIMARY KEY (`queststatusmobid`),
KEY `queststatusid` (`queststatusid`),
CONSTRAINT `queststatusmobs_ibfk_1` FOREIGN KEY (`queststatusid`) REFERENCES `queststatus` (`queststatusid`) ON DELETE CASCADE ON UPDATE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=utf8 ROW_FORMAT=DYNAMIC;
So,when I update the queststatusid of table queststatus, I use these command because the queststatusid reached the maximum of INT:
SET foreign_key_checks = 1;
SET #newid=0;
UPDATE queststatus SET queststatusid=(#newid:=#newid+1) ORDER BY queststatusid;
this command should makes queststatusid of table queststatusmobs change when queststatusid of of table queststatus update, but it doesn't.
It shows:
ERROR 1452 (23000): Cannot add or update a child row: a foreign key constraint fails (`twms`.`queststatus`, CONSTRAINT `queststatus_ibfk_1` FOREIGN KEY (`characterid`) REFERENCES `characters` (`id`) ON DELETE CASCADE ON UPDATE CASCADE)
I have deleted all useless foreign key which not in queststatus by using this command first:
DELETE FROM queststatusmobs WHERE queststatusid not in (SELECT queststatusid FROM queststatus);
How can I solve this problem?

Answer 1

You didn't have that particular id is not available on your characters table.
First you insert characters table id and used that id as a foreign key on queststatus table.
Or
Remove the foreign key reference from queststatus.

Answer 2

You might not able to change the id if you have a foreign key against it as it validate vice versa. You will either have to disable the foreign key checks or consider about changing the data type to BIGINT. That will be the most appropriate thing instead of trying to modifying the data.
To disable the foreign key check:
SET foreign_key_checks = 0;
Or else you can drop and create the foreign key