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Posted by Neeper on 08/01/07 05:25
I'm not sure what you mean by items not being part of the tree. Could
you give me an example of how I would do this.
On Tue, 31 Jul 2007 10:34:28 +0200, gosha bine <stereofrog@gmail.com>
wrote:
>On 31.07.2007 09:18 Neeper wrote:
>> I'm having trouble coming up with a query to count the number of total
>> items each subcategory with the lowest cost (CPU item).
>>
>> I'd like to be able to display the total in my pages like so using
>> PHP.
>>
>> Automotive (4 items)
>> - Cars (2 items)
>> - Trucks (2 items)
>> - Vans (0 items)
>> Electronics (6 items)
>> - Digital Cameras (0 items)
>> - Portable Audio (3 items)
>> - Home Theatre & Projectors (0 items)
>> - TV, DVD & VCR Players (3 items)
>> - Sound Systems & Components (0 items)
>
>Getting the count a subitems is trivial with nested sets:
>
>count of subnodes for some node = (rgt - lft) div 2
>
>The problem is that "items" are not part of the tree (may I ask why?)
>
>So, you need to get all categories first that are below the given
>category and then get items from those categories:
>
>SELECT COUNT(*)
> FROM items
> INNER JOIN categories
> ON items.category_id = categories.category_id
> WHERE
> categories.lft BETWEEN $CURRENT_LEFT AND $CURRENT_RIGHT
>
>(untested)
>
>BTW, this is a rather sql question than php, you'd probably get better
>answers in the mysql group.
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