Loop Structure

Hey,

I am trying to figure out how to structure a set of loops which will display the sub levels of several items to an infinite depth. I hate a database filled with items. Each item can have a "sub item". The ID of the parent is stored in the sub item. I want to loop through all of the "super items", then display all of their sub items and all of their sub items sub items. Let's say, for example, I had this:

- Super Item
   - Sub
       - Sub
           - Sub
           - Sub
           - Sub
       - Sub
-Super Item
   - Sub

Code (markup):

And so on. So, what I need is pseudocode or PHP code which shows how one would set up a loop to go through all of these items, assuming I had them stored in the database like this:

id                 parent
1                  -       
2                  1
3                  2
4                  2
5                  3
6                  5

Code (markup):

 

By the sounds of your problem I don't think it's loops you require, but a recursive function.

 

Since I'm on my lunch break, I coded up an example:

<?php
showAllItems();

function showAllItems($parent = 0, $space = '') {
    $query = mysql_query('SELECT name, id FROM items WHERE parent = "'.$parent.'"'); 
    
    while ($row = mysql_fetch_assoc($query)) {
        echo $space . '- ' . $row['name'] . "\n";   
        showAllItems($row['id'], $space . "\t");
    }
}
?>

PHP:

 

Hmm, looks like that's a lot simpler than how I thought it would be. I tested it and it works fine. Thanks! I'll post again if I see any problems with it, but I think it will do.