Laravel query builder for recursive results? E.g. id, parent_id

Question

So I have data structured like this:

id|parent_id|name
1 |null     |foo
2 |1        |bar
3 |2        |baz

So basically foo->bar->ba

Answer 1

I modified tiffanyhwang solution and turned it into a non-static method and included a attribute accessor to make it easier to get results.

public function ancestors()
{
    $ancestors = $this->where('id', '=', $this->parent_id)->get();

    while ($ancestors->last() && $ancestors->last()->parent_id !== null)
    {
        $parent = $this->where('id', '=', $ancestors->last()->parent_id)->get();
        $ancestors = $ancestors->merge($parent);
    }

    return $ancestors;
}

and accessor to retrieve a collection of ancestors from model attribute

public function getAncestorsAttribute()
{
    return $this->ancestors();
    // or like this, if you want it the other way around
    // return $this->ancestors()->reverse();
}

so now you can get ancestors like this:

$ancestors = $model->ancestors;

and since its a Collection, you can now easily do for example this:

echo $model->ancestors->implode('title',', ');