Kohana 3.3 ORM - how to find all ancestors in a tree (self-referencing table)

Question

How to find all the ancestors (not only direct parent) of a record with the following model:

class Model_Category extends ORM {

protected $_belongs_to = array(
        'parent' => array('model' => 'Category', 'foreign_key' => 'category_id'),
);

protected $_has_many = array(
        'children' => array('model' => 'Category', 'foreign_key' => 'category_id'),
);

$category->parent->find() is only giving the direct parent and even when trying to fetch the parent of the parent with a recursive function it throws Kohana_Exception: Method find() cannot be called on loaded objects.

This occurs so natural to me that I guess there must an easy way to do it - I'm not sure if it's me or the lack of documentation on ORM relations - halp!

score 1 · Answer 1 · answered May 06 '13 at 09:18

1

You should be able to do this with a recursive function or a while loop

$current = $category;
while ($current->parent->loaded())
{
    //save $current
    $current = $category->parent;
}

answered May 06 '13 at 09:18

kero

10,647
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biakaveron · Answer 2 · 2013-05-06T17:19:25.020

1

Use Nested Sets. For example, https://github.com/evopix/orm-mptt. It has special methods like parents(), children(), siblings() etc. Of course, this requires modifications in your DB table.

edited May 06 '13 at 17:19

answered May 06 '13 at 12:35

biakaveron

5,493
1
16
20

score 0 · Answer 3 · answered May 06 '13 at 01:31

Ok, turns out the related models actually ARE included, cause if you do

$category->parent->parent->name it will be the name of the grand-parent of $category.

My problem was that I was printing $category->parent->as_array() and expecting to see the parent relations in the (multidimensional) array which simply appears not to be the case with kohana.

Kohana 3.3 ORM - how to find all ancestors in a tree (self-referencing table)

3 Answers3