[tmql-wg] subjectIndicatorRef and resourceRef in TMQL

Lars Marius Garshol larsga@ontopia.net
Thu, 18 Mar 2004 16:33:20 +0100

* Rani Pinchuk
| I quoted the wrong line of Steve in his email... One sentence before
| he writes about source locators. According to XTM 1.1 they are
| connected to the IDs of the elements (although I am not sure how
| 0..* source locators are mapped to one id). This was the context of
| my question.

Oh, I see. We do query by source locators in the existing use cases.
The mapping does not go from source locators to ids, but the other
way. So every id of an element that has a corresponding item type
turns into a source locator. This only gives 0..1 source locators per
item, of course. However, items can be merged, and this is how they
can wind up with many source locators.

Try loading this LTM file in the Omnigator, and I think you'll see
what I mean. (Look at the source locators at the bottom of the topic

  [topic1 = "Topic1" @"http://psi.example.com/#foo"]
  [topic2 = "Topic2" @"http://psi.example.com/#foo"]
  [topic3 = "Topic3" @"http://psi.example.com/#foo"]
  [topic4 = "Topic4" @"http://psi.example.com/#foo"]
  [topic5 = "Topic5" @"http://psi.example.com/#foo"]
  [topic6 = "Topic6" @"http://psi.example.com/#foo"]

| But I am not sure why you write that we used source locators in the
| use case solutions. 

That's what is used for the direct references to the typing and
scoping topics, as well as the individual topics. So in the query

  instance-of($PERSON, person)?

the "person" token actually expands to

  <base locator of topic map>#person

and the topic with this source locator is what is found and used in
the query.

| Did we have a source locator for base name, occurrence or
| association? 

There were no examples of that, no. I think there should have been,
but we didn't do it.

| Should TMQL be able to refer to, for example, a base name by its
| source locator?

Yes, IMHO it should.

Lars Marius Garshol, Ontopian         <URL: http://www.ontopia.net >
GSM: +47 98 21 55 50                  <URL: http://www.garshol.priv.no >