[sc34wg3] Towards TMDM 3.0

[Lars Marius Garshol]

* Rani Pinchuk
>
> Thanks for taking your time with this.

No worries. This is saving us loads of precious meeting time. :-)

> Let's assume that we merge topic A and topic B because of any reason
> (equal PSI, manually merge...). We collect the two item identifiers  
> of A
> and B. The fact that we collected the item identifiers might help us  
> to
> merge to a third topic C.
>
> How exactly? This topic C will not have the same item identifier as  
> A or
> B (as the IRI is different). How could we possibly use this collection
> of item identifiers for future merges?

I think you should not focus on merging so much. TMDM gives you a  
property in which to store item identifiers, and XTM 2.0 and CTM tell  
you to put IDs there. This is done so that ID references will match up  
during import of XTM/CTM files.

We could of course throw away item identifiers after the import, but  
have decided not to, for a number of reasons.

  (1) It means all topics can have some kind of identifier, without
      this having to be a subject identifier, which is useful in a  
number
      of situations, from CXTM testing to web service protocols.

  (2) It means you can refer to topics that don't have a PSI or subject
      locator. When people write queries that use IDs to refer to
      topics that's because preserving item identifiers means you still
      have the IDs available.

  (3) It helps with merging, in a few, very limited cases, like when
      you're merging a.xtm with b.xtm and both of those include a
      common c.xtm.

--Lars M.
http://www.garshol.priv.no/blog/
http://www.garshol.priv.no/tmphoto/