CakePHP & MySQL Workbench relations

To start designing databases for CakePHP application firstly you need to be aware of distinctions between database relation types in MySQL  and model associations in CakePHP.

MySQL tables relationship CakePHP objects association
one-to-one non-identifying relationship hasOne
one-to-many non-identifying relationship hasMany, belongsTo
one-to-one identifying relationship not supported*
one-to-many identifying relationship not supported*
many-to-many identifying relationship hasAndBelongsToMany

* As there is no multiple-column primary key support in CakePHP it can be said that there is no support for 1:1 identifying and 1:n identifying relationships. The only exception is associated model with one column primary key which is relation foreign key at the same time

Screenshot below presents simple EER diagram (I have highlighted the Workbench relationships creator area in red):

Relationship description MySQL tables relationship CakePHP objects association
Each user may have only one profile page.
Each profile page is associated with one user.
users <-> profile_pages
(one-to-one non-identifying relationship)
User hasOne ProfilePage
Each article can be commented many times.
Each comment is created by a User.
Each user can create many comments.
articles <-> comments
(one-to-many non-identifying relationship)

users <-> comments
(one-to-many non-identifying relationship)

Article hasMany Comment,
Comment belongsTo Article,

User hasMany Comment,
Comment belongsTo User

Each user can like many articles.
Each article can be liked by many users.
users <-> users_articles <-> articles
(many-to-many identifying relationship)
User hasAndBelongsToMany Article

As I mentioned before it’s worth to use CakePHP naming convention during the design process. Once you’ve got proper database schema you can easily generate plain source code of your application. In other words MySQL Workbench + CakePHP code generator can be used as ORM (Object-relational mapping) design tool.

Via Rocketmill

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