Question

I have two tables. First table is a table of categories called categories, the second is a table of documents called documents. I’m trying to create a join table that will allow multiple categories to be applied to multiple documents and bake it all in seconds with CakePHP (to which I am a noob).

I’ve used mysql like this for the DB:

CREATE TABLE `categories` (
  `id` int(10) unsigned NOT NULL auto_increment,
  `cat_name` varchar(100) default NULL,
  PRIMARY KEY  (`id`)
) TYPE=MyISAM DEFAULT CHARSET=utf8;

CREATE TABLE `documents` (
  `id` int(10) unsigned NOT NULL auto_increment,
  `title` varchar(50) default NULL,
  `size` varchar(10) default NULL,
  `file` varchar(50) default NULL,
  `date` date default NULL,
  `created` datetime default NULL,
  `modified` datetime default NULL,
  `status` tinyint(1) NOT NULL default '0',
  PRIMARY KEY  (`id`)
) TYPE=MyISAM DEFAULT CHARSET=utf8;

CREATE TABLE `categories_documents` (
  `category_id` int(10) unsigned NOT NULL default '0',
  `document_id` int(10) unsigned NOT NULL default '0',
  PRIMARY KEY  (`category_id`,`document_id`)
) TYPE=MyISAM DEFAULT CHARSET=utf8;

…for the tables and was under the impression I got from what I read in the documentation that it would bake auto-magically. However I get lots of unknown column errors. I am wondering if I messed up on the naming conventions and if someone could put me right before I spent too long digging too deep?

Answer 1

The categories_documents will need an “id” field that needs to be the primary key. That should fix it. For more information, read the HABTM documentation.