Re: Modeling Data for XML instead of SQL-DBMS

mAsterdam wrote:
> dawn wrote:
> > mAsterdam wrote:
> >> Imagine discussing a weekly report:
> >> Q: How many candybars did we sell?
> >> A1: It is under sales, candybars: 504
> >> A2: It is on page 4, line 6: 504
> >>
> >> Both feel like navigating and pointing,
> >> both give the answer, but there is a difference.
> >> A1 is valid whatever media we are using.
> >> Not A2. A2 is implementation dependent.
> >> Not hardware dependent, but implementation
> >> dependent nevertheless.
> >>
> >> The hardware answer A3 would be: At .254
> >> millimeters from the start of the report, 5 cm
> >> from the top, 12 to the right on the flip side
> >> there are some ink-spots in the shape of 504.
> >> But first the question would require some serious
> >> translation.
> >>
> >> Good to have A3 gone, no?
> >> Now lets get back to getting A2 out.
>
> > OK, I understand this question.
>
> It is not a question. It is an illustration of grades
> of implementation dependency.

OK, but to me, there is still a question in this illustration.

> > ... I'm on the road for the coming week, and have appreciated the
> > dialog as it will help me figure out what I'm trying to ask and say in
> > a language that works for people starting in a different place than I.
>
> Remember you promised to rephrase the original question.

Yup.

> What is wrong with the OP is not just about differences
> in terminology or coming from another place; it is more
> basic. There are (some underlying, some obvious) assumptions
> which are false.

So says you ;-) Remember that you have learned something too in this exchange. Now you know there can be unnamed m:n relationships in an implementation of a logical data model.

> When these were brought to your attention
> earlier, and in this thread, you said you understand.

Yes, I recall that there was something new for me in the way you stated something, which did get at a difference that was not just semantic. I'll have to re-read.

> Sometimes you do, but sometimes - as soon as in the next post -
> you get back to the same, false assumption.

I think there is at least one assumption that I am not getting past that you think to be false and I don't think we are past that yet.

> Your IMO wrong understanding of the role of links is
> amazingly persistent.

Yes. Do you think I am the only person in the profession with this wrong understanding related to foreign key specifications and values? Foreign key specs are in the RM within a JOIN, but I know that what I am working with is not something that is readily appreciated by those working with the RM. I think the link spec is in the XML schema somewhat similarly to such link specs in a DBMS I work with. The <a href...> is different in that you link from a specific tuple-ish using a specific value rather than using a spec to get the value for the foreign key, and I think that is where the "pointer" description comes in, but I'm not sure.

> Please take your week
> to try to crunch it, and show that you did later on.

Would love to. This is "real" business, alas.

> <snip>
>
> > Thanks for the dialog and sorry to cut it off as I head out for a week,
> > but I do have enough to chew on.
>
> Have a nice week, cya.

Thanks, will do. Cheers! --dawn Received on Mon Oct 30 2006 - 03:37:06 CET