Re: TRM - Morbidity has set in, or not?

Dan wrote:

> Hi,
>
> Thanks for the response. I have a couple of follow-on questions.
>
> 1. "Not necessarily. The examples cited are rather small domains - a
> couple
> centuries worth of dates, states, words used in names or addresses -
> and
> the supported system would undoubtedly benefit by having these known
> ahead of time. But exhaustive enumeration isn't the only way one can
> specify a domain."
>
> Ok. Though understanding the alternative approaches to contrast to
> exhaustive enumeration would be useful, especially in light of the
> previous statement, "the values remain undisturbed and there's no need
> for index maintenance." Without enumeration, how does one claim that a
> set of values remain undisturbed?
>
> 2. "And CHAR (1000) is a trite example. How about JPEGs and MP3s and
> *.DOCs and XML."
>
> Let's stick with the trite example and demonstrate the effectiveness of
> the trite example first. Isn't this just a restatement of the age old
> claim that serialization of everything is the solution to everything.
> Honestly, Claude Shannon covered this effectively and from an entirely
> theoretical perspective in the 60's.
>
> 3. "Every domain should provide an operator that allows users to
> distinguish
> different values. If ordering is necessary: supply it. (And yes, TRM
> requires ordering; whether it is the same operator exposed to users is
> a different question, but I don't see any need for them to differ.) "
>
> This is an interesting and open question for me. It inevitably leads
> us back to whether domain and type are really the same thing. I tend
> to think not, and admittedly it runs against Date and many proponents
> here. An equivalent or equal domain can have different ordering
> operators in my opinion and considering symbolic values independent of
> some operators provides a greater degree of independence.

I disagree. If one has the same sets of representations but the less than operation is defined differently, one has a different type entirely. However, because the types have the same sets of representations, the type caste should have all of the cost of a no-op. Received on Wed May 17 2006 - 09:29:38 CEST