Joe Celko on Trees in SQL using nested sets. Search: linked lists, directed graphs, nested trees, SQL

• SQL Graph Algorithms – comparison of real-world solutions.

“I just picked up a copy and it looks great! You are right about the whole approach and my stuff stinks.” – Joe Celko

• SQLTeam: More Trees & Hierarchies in SQL – the depth and lineage optimizations are exactly what I’ve done in prior implementations
• Joe Celko, DBMS 4 parter (Mar-June 1996):
• A Look at SQL Trees
• SQL Lessons
• Nontraditional Databases
• When Good Data Goes Bad
• PostrgreSQL alpha implementation
• [Newsgroup links]

Semi-related: panelbox.org has Data Modelling links, jwz on message threading