Need Help w/ Unlimited depth categories

[Troy Lynch]

I'm working on writing a website which I need to have lists of
products listed in categories and subcategories, and need to keep
track of whats in the tree. Like how many products from the root all
the way down through the subcategories. I was thinking maybe in each
category it would have a field which lists all the root categories. I
hope this is a good explanation... it's kinda hard to explain I guess.
I figure there were probably some websites out there with methods or
something... Any help on this would be great.... Or a direction I can
do some researching..

Thanks

Troy

[Jochen Daum]

Hi Troy!

On 4 Jan 2004 16:18:16 -0800, dj********@yaho o.com (Troy Lynch) wrote:

I'm working on writing a website which I need to have lists of
products listed in categories and subcategories, and need to keep
track of whats in the tree. Like how many products from the root all
the way down through the subcategories. I was thinking maybe in each
category it would have a field which lists all the root categories. I
hope this is a good explanation... it's kinda hard to explain I guess.
I figure there were probably some websites out there with methods or
something... Any help on this would be great.... Or a direction I can
do some researching..

There should be heaps. Have a search for "tree php adjacent" or "tree
php nested set". These are the two most common methods.

HTH, Jochen
--
Jochen Daum - CANS Ltd.
PHP DB Edit Toolkit -- PHP scripts for building
database editing interfaces.
http://sourceforge.net/projects/phpdbedittk/

[Joaquim Amado Lopes]

Greetings.

One possibility is to have a field like "mother_categor y" in the
categories list. Each category would have a "mother", referred by it's
record ID or something like that. The category with mother_category =0
would be the root.

To count the products in a branch, create a recursive function that
adds the produtcs in every sub-category of the category you want to
start.

Something like:
Table categories:
id
category
mother_category <- categories.id

Table products:
id
cat_id <- categories.id
product

The function:
Parameter: top_id (id of the top category you want to consider)
How it works:
count the number of products with cat_id = top_id;
get the list of the sub-categories of the top_id category;
for each sub-category, it calls itself and adds the result to the
sum of products
Returns: the sum of products of that branch

Hope this helps,
Joaquim Amado Lopes