MySQL foreign key to another foreign key - mysql

Question

The idea is quite simple: i have three (or more) tables
- master_tbl (id, something, somethingelse)
- tbl2 (id, ....)
- tbl3 (id, ....)
Now what i want is a foreign key relationship, such as tbl3.id would point to tbl2.id and tbl2.id would point to master_tbl.id - all foreign keys are ON UPDATE CASCADE and ON DELETE CASCADE. What I'll get from this is that when I delete a record from tbl2, its tbl3 equivalent will get erased as well, but not master_tbl. When I delete a record from master_tbl, all three tables get erased.
When I try to create the foreign key on tbl3.id->tbl2.id, I get mysql error 150 - can't create table (the tbl2.id->master_tbl.id is already created).
My MySQL version is 5.1.46. Any ideas why this might be?
EDIT: table definitions
smf_members aka master_table
-- Table "smf_members" DDL
CREATE TABLE `smf_members` (
`id_member` mediumint(8) unsigned NOT NULL AUTO_INCREMENT,
`member_name` varchar(80) NOT NULL DEFAULT '',
`date_registered` int(10) unsigned NOT NULL DEFAULT '0',
`posts` mediumint(8) unsigned NOT NULL DEFAULT '0',
`id_group` smallint(5) unsigned NOT NULL DEFAULT '0',
`lngfile` varchar(255) NOT NULL DEFAULT '',
`last_login` int(10) unsigned NOT NULL DEFAULT '0',
`real_name` varchar(255) NOT NULL DEFAULT '',
`instant_messages` smallint(5) NOT NULL DEFAULT '0',
`unread_messages` smallint(5) NOT NULL DEFAULT '0',
`new_pm` tinyint(3) unsigned NOT NULL DEFAULT '0',
`buddy_list` text NOT NULL,
`pm_ignore_list` varchar(255) NOT NULL DEFAULT '',
`pm_prefs` mediumint(8) NOT NULL DEFAULT '0',
`mod_prefs` varchar(20) NOT NULL DEFAULT '',
`message_labels` text NOT NULL,
`passwd` varchar(64) NOT NULL DEFAULT '',
`openid_uri` text NOT NULL,
`email_address` varchar(255) NOT NULL DEFAULT '',
`personal_text` varchar(255) NOT NULL DEFAULT '',
`gender` tinyint(4) unsigned NOT NULL DEFAULT '0',
`birthdate` date NOT NULL DEFAULT '0001-01-01',
`website_title` varchar(255) NOT NULL DEFAULT '',
`website_url` varchar(255) NOT NULL DEFAULT '',
`location` varchar(255) NOT NULL DEFAULT '',
`icq` varchar(255) NOT NULL DEFAULT '',
`aim` varchar(255) NOT NULL DEFAULT '',
`yim` varchar(32) NOT NULL DEFAULT '',
`msn` varchar(255) NOT NULL DEFAULT '',
`hide_email` tinyint(4) NOT NULL DEFAULT '0',
`show_online` tinyint(4) NOT NULL DEFAULT '1',
`time_format` varchar(80) NOT NULL DEFAULT '',
`signature` text NOT NULL,
`time_offset` float NOT NULL DEFAULT '0',
`avatar` varchar(255) NOT NULL DEFAULT '',
`pm_email_notify` tinyint(4) NOT NULL DEFAULT '0',
`karma_bad` smallint(5) unsigned NOT NULL DEFAULT '0',
`karma_good` smallint(5) unsigned NOT NULL DEFAULT '0',
`usertitle` varchar(255) NOT NULL DEFAULT '',
`notify_announcements` tinyint(4) NOT NULL DEFAULT '1',
`notify_regularity` tinyint(4) NOT NULL DEFAULT '1',
`notify_send_body` tinyint(4) NOT NULL DEFAULT '0',
`notify_types` tinyint(4) NOT NULL DEFAULT '2',
`member_ip` varchar(255) NOT NULL DEFAULT '',
`member_ip2` varchar(255) NOT NULL DEFAULT '',
`secret_question` varchar(255) NOT NULL DEFAULT '',
`secret_answer` varchar(64) NOT NULL DEFAULT '',
`id_theme` tinyint(4) unsigned NOT NULL DEFAULT '0',
`is_activated` tinyint(3) unsigned NOT NULL DEFAULT '1',
`validation_code` varchar(10) NOT NULL DEFAULT '',
`id_msg_last_visit` int(10) unsigned NOT NULL DEFAULT '0',
`additional_groups` varchar(255) NOT NULL DEFAULT '',
`smiley_set` varchar(48) NOT NULL DEFAULT '',
`id_post_group` smallint(5) unsigned NOT NULL DEFAULT '0',
`total_time_logged_in` int(10) unsigned NOT NULL DEFAULT '0',
`password_salt` varchar(255) NOT NULL DEFAULT '',
`ignore_boards` text NOT NULL,
`warning` tinyint(4) NOT NULL DEFAULT '0',
`passwd_flood` varchar(12) NOT NULL DEFAULT '',
`pm_receive_from` tinyint(4) unsigned NOT NULL DEFAULT '1',
PRIMARY KEY (`id_member`),
KEY `member_name` (`member_name`),
KEY `real_name` (`real_name`),
KEY `date_registered` (`date_registered`),
KEY `id_group` (`id_group`),
KEY `birthdate` (`birthdate`),
KEY `posts` (`posts`),
KEY `last_login` (`last_login`),
KEY `lngfile` (`lngfile`(30)),
KEY `id_post_group` (`id_post_group`),
KEY `warning` (`warning`),
KEY `total_time_logged_in` (`total_time_logged_in`),
KEY `id_theme` (`id_theme`)
) ENGINE=InnoDB AUTO_INCREMENT=73 DEFAULT CHARSET=utf8;
cyp_users aka tbl2
-- Table "cyp_users" DDL
CREATE TABLE `cyp_users` (
`id` mediumint(8) unsigned NOT NULL,
`role` varchar(255) NOT NULL DEFAULT 'unregistered',
PRIMARY KEY (`id`),
CONSTRAINT `cyp_users_ibfk_1` FOREIGN KEY (`id`) REFERENCES `smf_members` (`id_member`) ON DELETE CASCADE ON UPDATE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
cyp_vip_users aka tbl3
-- Table "cyp_vip_users" DDL
CREATE TABLE `cyp_vip_users` (
`id` mediumint(8) NOT NULL,
`od` date NOT NULL,
`do` date NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

Answer 1

The ID's of tbl2 and tbl3 are different types.
Foreign Keys need to be of the same type.
tbl2.ID is UNSIGNED
tbl3.ID is SIGNED