Joe Celko's Trees and Hierarchies in SQL for Smarties, 2nd Edition

Chapter 8. Other Models for Trees

The models for trees and hierarchies discussed so far are not the only ones. Others use different approaches and properties of trees, some of which are hybrids of other models.

Keywords: adjacency list with self-references, subordinate adjacency list, hybrid models, adjacency and nested sets model, nested sets with depth model, adjacency and depth model, computed hybrid models, greatest common divisor, least common multiple

The models for trees and hierarchies discussed so far are not the only ones. Others use different approaches and properties of trees, some of which are hybrids of other models.

8.1. Adjacency List with Self-References

A slight modification of the usual adjacency list model is to include an edge ...