Re: Any new thoughts on OTLT (One True Lookup Table)
Date: Thu, 1 Apr 2004 07:50:45 -0500
Message-ID: <IZ6dnVmV5-OdjfHdRVn-sA_at_comcast.com>
Ben,
Another good response. I enjoy discussing this with you, even though our
two perspectives are quite divergent.
"ben brugman" <ben_at_niethier.nl> wrote in message
news:406bcb0a$0$5071$4d4ebb8e_at_read.news.nl.uu.net...
> The database can not be designed to hold the codes
> needed for the ecdf in a modelled way. So we have
> to revert to a 'generic' way of holding the codes.
.
.
.
> About your words, I think they are often true.
> Specifications are often drawn up during
> communication between 'specialists' and the
> 'users' of a product. Users are not used to
> 'exactly' define the way they are working.
Thanks for the clarification. It helps, but there's still a gap between what you are writing and what I'm understanding. I'm not going to try to say whose fault that is. I think it's inherent.
Let me try again.
So, what you store in the database schema is not a data model of the user
data, but a sort of "meta model" that can be used to model a wide variety
of data, so that you can postpone till later the actual binding of a data
model to the data. Is this a fair summary?
And this meta model is not understandable to a subject matter expert, it's
only understandable to another data modeler. Is this a fair inference from
your comments?
My experience is that subject matter experts are far less hazy about their
own data than they are about their own process. Their process is largely
unconscious, and becoming self conscious of process is as much fun for them
as "sensitivity training". But they've been working with data for a long,
long time, and they are good at it.
As far as constraints go, you have to work to get the constraints out of
them. Often, they have only a hazy idea of what the constraints are. But
show them an example of data that violates a constraint, and they'll
immediate verbalize what's wrong with it. To the user, bad data is like
pornography to one of the court justices: "I can't define it, but I know it