Re: Modelling objects with variable number of properties in an RDBMS

"paul c" <toledobythesea_at_oohay.ac> wrote in message news:vE39f.354857$1i.42920_at_pd7tw2no...
> Roy Hann wrote:
>
> > ...
> > Actually no, let's not. What you have re-invented here is the tired old
> > entity-attribute-value (EAV) design (much beloved of medical research
wonks
> > for some reason).
> > ...
>
> I have the same (limited) impression. I wonder why? Are they truly
> misguided or do they have some reason to think that the computer will
> discover relationships they can't pin down? Is finding those
> relationships the purpose of the research in the first place and are
> they just taking money for no good reason?

There is a very simple reason why people keep reinventing E-A-V.

They want all the benefits that go with structured data together with all the benefits that go with unstructured data. They aren't sophisticated enough to see the trade-off in advance.

They don't understand the down side of that design until after they have shot themselves in the foot.

After that, some of them learn, and do better on their next project. Others keep making the same mistake, over and over again, and blame the consequences on the tools they are using. Received on Sun Oct 30 2005 - 19:51:42 CET