>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...


-- 
PHP Database Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php

Reply via email to