NYCPHP Meetup

[Hans Zaunere]

Roland Cozzolino wrote on Thursday, October 20, 2005 5:09 PM:
> You can also use nested set theory.  This makes retrieval of parents,
> children, siblings, etc. extremely fast and efficient.  This also allows
> for an unlimited hierarchy.  The math is a bit more confusing at first,
> but quite trivial once you get it. The adjacency list model is
> significantly slower but much easier to understand.  A good link to help
> understand this is
>
http://www.intelligententerprise.com/001020/celko.jhtml?_requestid=1266295.
> Also note, that in Oracle, there is a specific function to deal with
> this ... postgres, mysql, sql server and others do not deal with
> hierarchical structures in flat format.  Hope this helps, although I am
> not sure what the question was in the first place.

Ahh, good old NSM...

New York PHP developed an implementation of NSM, pNSM, as part of the clew
project.

There is endless discussion on the NYPHP-Org mailing list, including
presentations and code here:

http://www.nyphp.org/content/presentations/nyphp/index.php?slide=2

http://cvs.nyphp.org/cvsweb.cgi/clew/lib/


---
Hans Zaunere / President / New York PHP
   www.nyphp.org  /  www.nyphp.com