Perhaps the book Joe Celko's Trees and Hierarchies in SQL for Smarties by Joe Celko would be of interest.

From the back cover:

In this book, Celko illustrates several major approaches to representing trees and hierarchies and related topics... These topics include hierarchical encoding schemes, graphs, IMS, binary trees, and more.

HTH,

planetscape

In reply to Re: modeling relationships by planetscape
in thread modeling relationships by punkish

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