Welcome to the Cookbook

Now that we have Profile data access from the User model, let’s define a belongsTo association in the Profile model in order to get access to related User data. The belongsTo association is a natural complement to the hasOne and hasMany associations: it allows us to see the data from the other direction.

When keying your database tables for a belongsTo relationship, follow this convention:

If a model(table) contains a foreign key, it belongsTo the other model(table).

We can define the belongsTo association in our Profile model at /app/models/profile.php using the string syntax as follows:

<?php

class Profile extends AppModel {
    var $name = 'Profile';                
    var $belongsTo = 'User';   
}
?>

1. <?php
2. class Profile extends AppModel {
3. var $name = 'Profile';
4. var $belongsTo = 'User';
5. }
6. ?>

We can also define a more specific relationship using array syntax:

<?php

class Profile extends AppModel {
    var $name = 'Profile';                
    var $belongsTo = array(
        'User' => array(
            'className'    => 'User',
            'foreignKey'    => 'user_id'
        )
    );  
}
?>

1. <?php
2. class Profile extends AppModel {
3. var $name = 'Profile';
4. var $belongsTo = array(
5. 'User' => array(
6. 'className' => 'User',
7. 'foreignKey' => 'user_id'
8. )
9. );
10. }
11. ?>

Possible keys for belongsTo association arrays include:

• className: the classname of the model being associated to the current model. If you’re defining a ‘Profile belongsTo User’ relationship, the className key should equal ‘User.’
• foreignKey: the name of the foreign key found in the current model. This is especially handy if you need to define multiple belongsTo relationships. The default value for this key is the underscored, singular name of the other model, suffixed with ‘_id’.
• conditions: An SQL fragment used to filter related model records. It’s good practice to use model names in SQL fragments: “User.active = 1” is always better than just “active = 1.”
• fields: A list of fields to be retrieved when the associated model data is fetched. Returns all fields by default.
• order: An SQL fragment that defines the sorting order for the returned associated rows.
• counterCache: If set to true the associated Model will automatically increase or decrease the “[singular_model_name]_count” field in the foreign table whenever you do a save() or delete(). If its a string then its the field name to use. The value in the counter field represents the number of related rows.
• counterScope: Optional conditions array to use for updating counter cache field.

Once this association has been defined, find operations on the Profile model will also fetch a related User record if it exists:

//Sample results from a $this->Profile->find() call.

Array
(
   [Profile] => Array
        (
            [id] => 12
            [user_id] => 121
            [skill] => Baking Cakes
            [created] => 2007-05-01 10:31:01
        )    
    [User] => Array
        (
            [id] => 121
            [name] => Gwoo the Kungwoo
            [created] => 2007-05-01 10:31:01
        )
)