recursive function in model is not returning values as it echo all values within function

recursive function in model is not returning values as it echo all values within function - Printable Version

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recursive function in model is not returning values as it echo all values within function - El Forum - 06-02-2010

[eluser]Unknown[/eluser]
Hi All,

i have write the function in a model which call it self as recursive call end to a basic condition it echo all values but didn't return value to me in controller.

please help. below i m writing code of my function please check and ask if there is any issue with this.

Code:
function get_upper_most_parent($page_id)

{

    $this->db->select('page_id,page_parent');

    $this->db->from('pages');

    $this->db->where('page_id',$page_id);

    $result=$this->db->get();

    $row=$result->row();

    $parent_id=$row->page_parent;

    if($parent_id==0)

    {

        return $page=$row->page_id;

    }

    else

    {

        $this->get_upper_most_parent($parent_id,1);

    }

}

Thanks in Advance

Regards

recursive function in model is not returning values as it echo all values within function - El Forum - 06-02-2010

[eluser]mddd[/eluser]
The problem is, that you don't do anything with the result of your recursive function. The function will call itself until it reaches 'parent_id=0'. The last recursion of the function will then return the correct id. But this 'return value' goes to the previous recursion. And that recursion doesn't do anything with the value!

I think the solution is simple:

Code:
// replace this:

$this->get_upper_most_parent($parent_id,1);

// with this:

return $this->get_upper_most_parent($parent_id);

That way, every recursion returns its result to the one before. And eventually: back to the main call you make to the model.

(Note: you are making a lot of calls to the database this way. I think there are quicker methods to get the main parent. For instance: if you know te maximum depth of your pages, you could join multiple times on the same table and check the correct parent in php. You'll need only 1 call to the database and fetch 1 row to do it).

recursive function in model is not returning values as it echo all values within function - El Forum - 06-02-2010

[eluser]Unknown[/eluser]
Thanks