Re: why hierarchy?
Date: 26 Jul 2006 12:44:48 -0700
Message-ID: <1153943088.821630.307190_at_i42g2000cwa.googlegroups.com>
paul c wrote:
>
> If you're making the claim, it is up to you to show how it so, not for
> others to refute it.
Agreed.
> I suspect the former isn't possible as it would
> necessarily require some unknown to become known for any demonstration
> to work. This would seem a fallacy if one agrees that the known can't
> also be unknown.
Yes, but it's not quite as hopeless as this makes it sound. We can identify what the possible space of schema changes are, and we can use empirical analysis to get an idea of how common each of various different kinds of changes are.
In my experience (unmeasured) , the most common kind of change is the adding of an attribute to an existing entity.
Marshall Received on Wed Jul 26 2006 - 21:44:48 CEST