Thank you for your response. see comments below... ----- Original Message ----- From: "Matt Neimeyer" <matt@neimeyer.org> > >I need to develop a tree-like pedigree of animals up to 5 generations. > >I know there are other attributes to the animal; but do I need anyother > >tables...assuming that I can develop all the code to generate these > >ancestors. > > >Animal > > ID > > Name > > > >Foal > > ID > > SireID > > DamID > > Would it be any more difficult to make a self-referential table? Like So? > If the information is unknown then the fields are blank otherwise the > SireID and DamID point back to the ID of another record in the same table. > > Animal > ID > Name > SireID > DamID > > I'm in the conceptual stage of a similar project for humans and this is the > approach I'm leaning towards. I'm planning on using something like this... > > Person > ID > Name > MotherID > FatherID > SpouseID > > The reason I chose this is that even though a lot of the Mother, Father and > Spouse fields might be "blank wasted space" I figured I'd be doing joins on > the two tables (three in my case with the additional one for spouse) so > often I'd be saving data storage space at the expense of data processing > power creating the joins on the fly every time I needed them. > > Just a thought... > > Matt > > P.S. If anyone sees any "evil" inherent in my design I'd love to know... This is an interesting idea, The spouse category interests me...Somehow I need to add a Litter enrollment table which would document the various litters...sires and dams and the whelping date. Lets compare progress...huh? Russell Griechen htttp://sportsmenafield.com -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
