James
Yes thats the ticket!
I especially like the description at the top of the first link.
'Nested sets rely on a demoralization of parts of the hierarchy'
There's probably something witty I could say about this concerning
politics but I don't want to start a flame war!
'modified preorder tree traversal' is a bit of a mouthfull and I am not
sure that 'nested sets' is the correct term either but at least the
descriptions make sense.
Thanks for those links.
Now to create a module!
Regards
Ian
James Coupe wrote:
ian <londonperlmong...@iandocherty.com> wrote:
* Every node has a left and a right value and a level
* For any given node, all of it's descendents left values lie between
the nodes left and right values.
* For a leaf node, it's right value equals it's left value + 1
* All children of a parent will therefore be those with node numbers
between the parents left and right values and one level deeper.
Nested Sets?
http://www.codeproject.com/KB/database/nestedsets.aspx
Some discussion here, although without giving a proper name to the
structure.
http://articles.sitepoint.com/article/hierarchical-data-database/2
