Path: utzoo!mnetor!uunet!husc6!mit-eddie!uw-beaver!tikal!slovax!flak
From: flak@slovax.UUCP (Dan Flak)
Newsgroups: comp.databases
Subject: Informix Brain Teaser
Message-ID: <2678@slovax.UUCP>
Date: 11 Jan 88 18:56:31 GMT
Distribution: na
Organization: R & D Associates., Tacoma, WA
Lines: 36

Here's a brain teaser for you folks using Informix 3.30. (I can't
validate SQL since I don't have it).

The schema looks like:

    database foo

    file family

    field name   type character 20 index primary
    field parent type character 20 index dups.

    end

The data entry is set up (using PERFORM) so that once the first record
is seeded into the database ("ADAM" or "EVE" if you prefer), all other
records validate from the "name" field to accept legal values for the
required "parent" field. Notice that the "index primary" in each field
forces each individual name to be unique.

The challenge:

    Write a progam using ACE and/or C which will accept as its
first argument the name of any ancestor, and produce a list of all
descendants for as many generations as are loaded in the database.

I've run across this problem working with "Task Organizations" with
the U.S. Army, but I could also see an application in genetics, 
railroad management (i.e. trains, and trains of trains), or any other
problem where the whole is equal to the sum of its parts, but those
parts aren't always permanently assigned.

I really would like to see how others have solved this problem.
-- 
                  {hplsla,uw-beaver}!tikal!slovax!flak
Dan Flak-R & D Associates,3625 Perkins Lane SW,Tacoma,Wa 98499,206-581-1322