Hierarchies - Topological Ordering Topics (Nested Sets) - Examples

These example scripts describe the technique of topological ordering of hierarchies. They start by setting up a working set of tables and continue with a working example of the enumeration algorithm followed by use cases of ancestor-descendent queries and computational hierarchies.

This material is referenced by presentation E12 of the IDUG EMEA 2010.

Take a look at the The Relational Taboo page for the original article circa 1992. Also refer to Joe Celko's books for the basics of the technique.

Setup and sample data script1.91 KB
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