Keith,
There are a number of posts and papers on tree structures , both in the
SQL list archives, and on Roberto Mello's resources at
techdocs.postgresql.org.
-Josh
______AGLIO DATABASE SOLUTIONS___________________________ Josh Berkus Complete
informationtechnology josh@agliodbs.com and data management solutions (415) 565-7293 for law firms, small
businesses fax 621-2533 and non-profit organizations. San Francisco