Re: Q: data modeling with inheritance

On Fri, Jul 03, 2009 at 05:37:20PM -0700, Reece Hart wrote:
> On Fri, 2009-07-03 at 11:29 -0700, David Fetter wrote:
>
> > I'm missing what you're doing here that foreign keys don't cover.
> > Could you send along your DDL?
>
> No DDL yet... I'm just in the thinking stages. FKs technically would
> do it, but would become unwieldy. The intention was to have
> subclasses of each of the variant, association, and phenotype
> tables. That leads to the polymorphic key problem.

How many (order of magnitude) are we talking about here?

> > Just generally, I've only found table inheritance useful for
> > partitioning.  "Polymorphic" foreign key constraints can be
> > handled other ways such as the one sketched out below.
>
> That answers the question -- I do want polymorphic foreign keys.
> Dang.

It solved some real-world problems I had at the time, mostly from the
game space.  My biology is a little rusty :/

Cheers,
David.
--
David Fetter <david@fetter.org> http://fetter.org/
Phone: +1 415 235 3778  AIM: dfetter666  Yahoo!: dfetter
Skype: davidfetter      XMPP: david.fetter@gmail.com

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