Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!uw-beaver!uw-june!uw-entropy!uw-apl!rudd
From: rudd@uw-apl.UUCP (Charlie Rudd)
Newsgroups: comp.databases
Subject: Using SQL to support hierarchical/spatial data structures
Keywords: Spatial, GIS
Message-ID: <231@uw-apl.UUCP>
Date: 17 May 89 15:25:04 GMT
Sender: news@uw-apl.UUCP
Organization: UW Applied Physics, Seattle
Lines: 31


Greetings:

I am looking for practical ways of extending SQL (ala Ingres)
to support hierarchical/spatial data structures. Specifically:

 	1. Ways of implementing self-referencing hierarchical structures
           (e.g., "Bill of Materials"). 
		a. What tables do you use?
	        b. How do you implement retrievals?

        2. a basic approach to encoding a spatial coordinate system 
           (e.g., latitude/longitude) as a reference to spatial objects that
           would facilitate:
                a. quickly, easily changing granularity of referenced spatial 
                   objects, and
	        b. doing spatial-based queries/operations on spatial 
                   objects.

My hope is to support the handling of environmental data about various
ocean reqions currently residing in various discrete databases.
I would be interested in references to books, papers, first-hand experience
etc. 

Given some indication of interest by others, I'll summarize/repost results.

Charles Rudd (206-543-1644)
Applied Physics Lab
University of Washington
Seattle WA 98102
rudd@slew.apl.washington.edu