Yii Relations

USER table
- id
- name

POST table
 - id
 - user_id         REFERENCES User.id
 - content

PROFILE table
 - id
 - user_id         REFERENCES User.id
 - profile_info
KEY POINT: A BELONGS_TO relation says that a field in this model points to the primary key in another model; in this case, the current model owns the linking field.

KEY POINT: A HAS_ONE relation says that some other model has a linking field pointing to this model's primary key; in this case, the related model owns the linking field.

Let's put these in context (numbered for reference)

// Post model relations
1.   'user'    => array(self::BELONGS_TO, 'User',    'user_id'),

// Profile model relations
2.   'user'    => array(self::BELONGS_TO, 'User',    'user_id'),

// User model relations
3.   'posts'   => array(self::HAS_MANY,   'Post',    'user_id'),
4.   'profile' => array(self::HAS_ONE,    'Profile', 'user_id'),