mysql add foreign key constraint error - mysql

Question

I have two tables which I'd like to connect with foreign key constraint
For some reason, when I try to do it, it fails and and says: #1215 - Cannot add foreign key constraint
Here is my first table:
CREATE TABLE `zmaneyhayom` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`zman_id` varchar(255) NOT NULL,
`tempHour` tinyint(1) NOT NULL,
`tempHourType` varchar(255) NOT NULL,
`tempHourNum` double NOT NULL,
`tempMinutes` tinyint(1) NOT NULL,
`tempMinutesType` varchar(255) NOT NULL,
`tempMinutesNum` double NOT NULL,
`regularMinutes` tinyint(1) NOT NULL,
`regularMinutesNum` double NOT NULL,
`equivalentMinutes` tinyint(1) NOT NULL,
`equivalentMinutesNum` double NOT NULL,
`degreesBelowHorizon` tinyint(1) NOT NULL,
`degreesBelowHorizonNum` double NOT NULL,
`beforeAfter` varchar(6) NOT NULL,
`riseSet` varchar(4) NOT NULL,
PRIMARY KEY (`id`),
UNIQUE KEY `zman_id_2` (`zman_id`),
KEY `zman_id` (`zman_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8
And this table holds ID and name, which eventually the ID in this table is the name for the previous table (zman_id column):
CREATE TABLE `zmaneyhayomlabels` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(255) NOT NULL,
PRIMARY KEY (`id`),
UNIQUE KEY `id` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8
This is the code I'm attempting in order to create the constraint:
ALTER TABLE `zmaneyhayom` ADD FOREIGN KEY ( `zman_id` ) REFERENCES `luah_v2`.`zmaneyhayomlabels` (
`id`
) ON DELETE NO ACTION ON UPDATE NO ACTION ;
I have no idea why it's failing :/
What I want is that whenever I go on phpmyadmin and go to the first table, instead of typing some id in zman_id I will have a select box which I can select a name (which is stored in the second table) but the value it will store will be the ID.

Answer 1

they are not same type id is INT and zman_id is varchar.
you can change this
`zman_id` varchar(255) NOT NULL,
to
`zman_id` int(11) NOT NULL,