Andrew,
> Its a way of representing a tree with right-left pointers in each
> record (basically re-inventing a hierarchical database
> in a relational model...). A good description is in Joe Celko's SQL
> For Smarties book. Selection is very fast because
> any node's children have node ID's between the right and left nodes of
> said node, so there's no mucking about
> with connect by and what not. There's a synopsis linked at the PG
> Cookbook pages (http://www.brasileiro.net/postgres/cookbook),
> but the cookbook seems to off-line (I think I'll offer to mirror it -
> this happens frequently). There's another description at
> http://www.intelligententerprise.com/001020/celko.jhtml?
> _requestid=65750.
I have a full implementation of this. I was going to do it as a magazine
article, so I've been holding it off line. However, publication seems to be
indefinitely delayed, so I'll probably post it on TechDocs as soon as I have
time.
--
-Josh Berkus
Aglio Database Solutions
San Francisco