cakephp CakePHP3 Coding Tips Model Associations in CakePHP
Example
There are 4 types of associations(relationships) we can define in CakePHP
class PostsTable extends Table {
public function initialize(array $config) {
// table initialization code should be here
$this->belongsTo('Authors', [
'className' => 'Authors',
'foreignKey' => 'author_id',
'joinType' => 'INNER',
]);
$this->hasMany('Tags');
$this->hasOne('Categories');
$this->hasAndBelongsToMany('Topics');
}
}
In above example, you can see 4 types of relationships
Post belongs to Author (One to One), it means in posts table has one foreign key author_id which is associated with id of authors table.
Post has many Tags (One to Many), it means in tags table has one foreign key post_id which is associated with id of posts table.
Post has one Tags (Many to One or One to One), it means in posts table has one foreign key category_id which is associated with id of categories table.
Post has and belongs to Topics (Many to Many), this is many to many relationship between posts and topics table. for maintain many to many relationship must need to create third table, table, table name should be posts_categories. Fields of this table as mentioned below
- id (primary key of table)
- post_id (foreign key of
poststable) - topic_id (foreign key of
topicstable)
