Sun, 27 Apr 2003 15:43:34 +0200
Lars Marius Garshol wrote:
> * Jan Algermissen
> | The following email discussion is taken from the threat "Questions
> | on N0396: (8) Conformance":
> Hey, Jan, are you sure you mean what you wrote there? :-)
Duh...I typed 'd' first, then used 't'...oh well ;-)
> | Clearly, there are portions of both, N0393 and N0396 that do make
> | sense to constrain applications (e.g. merging behaviour, value
> | equality...), but what is the purpose of the conceptual data model?
> | We need it, sure, but what for?
> You lost me here, I'm afraid. What do you mean by "the conceptual data
N0396 says in the introduction:
"Topic maps may be represented in many ways: using topic map syntaxes in
files, inside databases, as internal data structures in running programs,
and even mentally in the minds of humans. All these forms are different
ways of representing the same abstract structure, and it is that structure
that is defined in this document, in the form of a data model."
For me "the same abstract structure...in the form of a data model." means that
N0396 defines a 'conceptual data model' or call it 'abstract information structure'.
What I am up to is to find the purpose that this structure fulfills. Since it does
not make sense to use it to constrain the internals (I could create an implementation
that never actually performs a merge internally but makes it look as if it did from
the outside) then what is it good for (not the SAM as a whole, just the data structure)?
Is it purely a matter of providing a language to 'say' the important stuff (e.g.
merging rules)? Is it purely illustrative?
To take this out of TM context: What purpose does the entity relationship model
fulfill in RDBMS land?
Jan Algermissen http://www.topicmapping.com
Consultant & Programmer http://www.gooseworks.org