Yii Relational Query with 'through' - database

Question

Good evening,
In this page (http://www.yiiframework.com/doc/guide/1.1/en/database.arr#relational-query-with-through) it's described how to get all comments for all users of a particular group using 'through':
class Group extends CActiveRecord
{
...
public function relations()
{
return array(
'roles'=>array(self::HAS_MANY,'Role','group_id'),
'users'=>array(
self::HAS_MANY,'User',array('user_id'=>'id'),'through'=>'roles'
),
'comments'=>array(
self::HAS_MANY,'Comment',array('id'=>'user_id'),'through'=>'users'
),
);
}
}
How can I do exactly the opposite? That is, get the group of the user who made a particular comment (Comment Model basically).
So far, I'm not even able to reach 'role' table:
'user' => array(self::BELONGS_TO, 'User', 'user_id'),
'roles'=>array(self::HAS_MANY, 'Role', array('id'=>'user_id'), 'through' => 'user') // shouldn't it join User.id to Role.user_id ?
It's raising the following error: 'Column not found: 1054 Unknown column 'user.user_id' in 'where clause'. And it seems related to the first line, not the second...
Any ideas?
Sincerely,
Apidcloud

Answer 1

As you want to get the group of the user who made a particular comment. You have to add these relation in the comment model.
public function relations()
{
// NOTE: you may need to adjust the relation name and the related
// class name for the relations automatically generated below.
return array(
'user' => array(self::BELONGS_TO, 'User', 'user_id'),
'roles'=>array(
self::HAS_ONE,'Role',array('id'=>'user_id'),'through'=>'user'
),
'group'=>array(
self::BELONGS_TO,'Group','group_id','through'=>'roles'
)
);
}
And view file you can get group name like this.
<?php echo CHtml::encode($data->group->name); ?>
Hope this will help you.