[topicmapmail] Topic Maps in a DBMS

[Thomas Flemming]

[ Alexander Johannesen ]
> Marc de Graauw <marc@marcdegraauw.com> wrote:
> 
> > I'm curious what kind of activity my article spawned - do you have
> > experience with extending RDBMS's with TM's along the lines I
> > sketched?
> 
> I'd still like someone to create a workable and plugable RDBMS system
> for topic maps that coupld be used for a lot of times when the
> customer has invested a lot in their RDBMS and feel reluctant to
> start from scratch with something mystiqe as TM. :)

Why not define several RDBMS models for storing topicmaps? The simplest
could be named "Level 1 RDBMS topicmap" like the different levels of 
JDBC drivers.

Marc de Graauw's simple model with only 6 tables
http://www.xml.com/pub/a/2003/03/05/tmrdb.html could be
defined as the standard Level 1 RDBMS TopicMap. It lacks
scopes and some of the other advanced topicmap features, 
but for many applications it's enough. You can't merge in
other topicmaps but you can export your data as a topicmap. 

Level 2 RDBMS TopicMap could be a database model similar to the one mentioned
in http://tinyurl.com/jfrn with 17 tables. To merge two databases with this
model, you proabably would generate a third database. 

A third level could be defined when someone defines a complete RDBMS
model for TopicMaps. 

Met vriendelijke groet ;)
Thomas Flemming 
University of Oslo/USIT
http://folk.uio.no/thomasfl