Kohana ORM访问信息

Question

I'm trying to learn how to access and display information. I have categories, forums, topics, and posts. forums belongs to categories, topics belongs to forums, and posts belongs to topics. I don't know how to access posts.

Tables:

categories {category_id, category_title}
forums {forum_id, forum_title}
categories_forums {id_category, id_forum}
topics {topic_id, topic_title}
forums_topics{id_forum, id_topic}
posts {post_id, post title}
topics_posts {id_topic, id_post}

Models:

class Model_Category extends ORM {

protected $_primary_key = 'category_id';

protected $_has_many = array(
    'forums'=> array(
        'model' => 'forum',               
        'through' => 'categories_forums',   
        'far_key' => 'id_forum',     
        'foreign_key' => 'id_category'  
    ),
  );
}

class Model_Forum extends ORM {

protected $_primary_key = 'forum_id';

 protected $_belongs_to = array(
    'categories'=> array(
        'model' => 'category',                
        'through' => 'categories_forums',   
        'far_key' => 'id_category',       
        'foreign_key' => 'id_forum'   
    ),
);

protected $_has_many = array(
    'topics'=> array(
        'model' => 'topic',                
        'through' => 'forums_topics',    
        'far_key' => 'id_topic',       
        'foreign_key' => 'id_forum'   
    ),
  );
}

class Model_Topic extends ORM {

protected $_primary_key = 'topic_id';

protected $_belongs_to = array(
    'forums'=> array(
        'model' => 'forum',                
        'through' => 'forums_topics',    
        'far_key' => 'id_forum',       
        'foreign_key' => 'id_topic'   
    ),
);

protected $_has_many = array(
    'posts'=> array(
        'model' => 'post',                
        'through' => 'topics_posts',    
        'far_key' => 'id_post',       
        'foreign_key' => 'id_topic'   
    ),
  );
}

class Model_Post extends ORM {

protected $_primary_key = 'post_id';

protected $_belongs_to = array(
    'topics'=> array(
        'model' => 'topic',                
        'through' => 'topics_posts',    
        'far_key' => 'id_topic',       
        'foreign_key' => 'id_post'   
    ),
  );
}

So far I have the following:

foreach ($categories as $category) :
echo $category->category_title;
foreach ($category->forums->find_all() as $forum) :
echo $forum->forum_title;
$num_topics = $forum->topics->count_all(); echo $num_topics;
$num_posts = $forum->topics->posts->count_all(); echo $num_posts;
endforeach;
endforeach;

The problem is echo $num_posts displays 0. I'm guessing I'm accessing posts wrong. How do I do it?

Answer 1

1. You must iterate topics to get the posts.
2. After a count_all() Kohana reset the Model.

You must do it like this:

    $topics = $forum->topics->find_all()->as_array();

    $num_topics = count($topics);

    foreach($topics as $topic) 
    {
        $num_post_in_topic = $topic->posts->find_all()->count();
    }