[topicmapmail] occurrence abuse ? Was: [geolang-comment] Firstproposals for ISO 639 and 3166 available

[Kal Ahmed]

On Thursday 22 August 2002 09:45, Lars Marius Garshol wrote:
> * Lars Marius Garshol
>
> | I haven't formally raised this issue yet, but I think we will have
> | to extend occurrences so that they may be typed. Obvious types
> | include booleans, numbers, and dates, while less obvious types are
> | things like XML. These things will be needed for various purposes,
> | querying, validation, sorting, and presentation among them.
>
> * Kal Ahmed
>
> | Do we *really* have to go there ?
>
> I think so. How do you do numeric operations like sums and averages,
> less than/greater than tests, etc without these data types?

Are those things that you would regard as features of a "topic map engine=
" as=20
opposed to a "topic map application" ?

> Also, if
> an occurrence is supposed to hold a number I guess it would be nice to
> be able to require that.
>

I'm not against datatypes, just against reinvention of that particular wh=
eel.

> | It quickly becomes an awful mess.
>
> Uh, yes. It will certainly add complexity.
>
> | Can't we just allow XML markup in the content of an occurrence and
> | let those that want datatyping use XML Schema datatypes ?
>
> I would prefer to reuse the datatypes from elsewhere, rather than
> having us define our own.

I'm glad to hear that.

> Some common subset of the SQL, XML Schema,
> and RDF datatypes (when RDF gets datatypes) would be perfect, since
> the datatypes would then be implementable no matter what sort of
> storage mechanism you use.

This is the kind of mess that I am worried about. A "common subset" means=
 (to=20
me)  "something different from all the other datatyping standards out the=
re".=20
How will you work out that common subset ? How many hours will be spent o=
n=20
doing that instead of working on other stuff ? Whereas if one were just t=
o=20
lift the restriction on the content of inline occurrences, one could inse=
rt=20
any arbitrary (and if necessary) typed, structured information.

Cheers,

Kal
--=20
Kal Ahmed, techquila.com
XML and Topic Map Consultancy

e: kal@techquila.com
p: +44 7968 529531
w: www.techquila.com