Re: Identity modelling

Marshall Spight wrote:
> dawn wrote:
> > Marshall Spight wrote:
> > >
> > > The distinguishing characteristic of content-based addressing
> > > is that data is addressed by some part of the data. Note
> > > that nothing *in* the html file identifies the html file.
> > > Most html files don't contain their url. So the URL is a pointer.
> >
> > I disagree. If one is modeling this data (and I think the referent of
> > "this data" might be the problem) and taking a very traditional
> > key-value approach with your data model, then the URL is surely a key.
>
> Modelling has nothing to do with it. This is purely a syntactic issue.

OK
>
> > I think your use of "pointer" here is very extreme
>
> I'm okay with that. :-)

[Quoted] [Quoted] Good. I myself shy away from such extremes ;-)
>
> > -- miles away from memory locations, for example.
>
> Granted.
>
>
> > There is nothing hidden or behind the scenes about a URL.
> > One issue I see is that you opted to talk about
> > modeling the html file, rather than all of the data under
> > consideration.
>
> I don't understand this statement. Did I say it needed to be hidden?

[Quoted] No, I was still referring to lines between what is a pointer and what is not. A value that is entered by humans routinely is not a likely candidate to be termed a "pointer" unless every value that points is a pointer.

>
> > So, perhaps if you add in the URL to the data you are
> > modeling, you will agree that it is, indeed, a key?
>
> Yes: if the URL was *in* the html, and we accessed it by
> looking for an html document with a specified URL, then it
> would be a key.

Would you be OK with saying that the URL is a key TO the full web page, [Quoted] [Quoted] while not being a key OF the html page? It sounds like you would be OK with that iff we defined the full web page to include both the URL and [Quoted] the html (not typically how "web page" is used).

[Quoted] [Quoted] When working with key-value pairs, it is common to say that the key is a key to that value. Why would we want to redefine that term to make that inaccurate? Since that terminology has been around longer than relational theory (I think), I think we can permit keys in key-value pairs to be called keys so as not to muddy the language unnecessarily. [Quoted] [Quoted] Maybe we should just say that the URL is a key, but not a relational key to the web page? --dawn

>
> Marshall
Received on Thu Sep 01 2005 - 04:08:55 CEST