W3C home > Mailing lists > Public > public-rdf-dawg@w3.org > January to March 2007

Re: definition of INDISTINCT

From: Eric Prud'hommeaux <eric@w3.org>
Date: Fri, 16 Mar 2007 15:40:37 -0400
To: Jeen Broekstra <j.broekstra@tue.nl>
Cc: public-rdf-dawg@w3.org
Message-ID: <20070316194037.GY13846@w3.org>
* Jeen Broekstra <j.broekstra@tue.nl> [2007-03-16 17:39+0100]
> 
> Alright, nitpicking a bit:
> 
> Eric Prud'hommeaux wrote:
> 
> > persuant to
> >   ACTION: ericP to draft text about a LOOSE keyword and run it by w3
> >   folks to see if we're abusing the "at risk" mechanism.
> > I drafted this section. It was slightly more awkward to not have an
> > ALL to lean on, but I think this is pretty well defined:
> > 
> > 9.4 INDISTINCT
> 
> When/where was this term introduced?
> 
> If we decide to add this, I think I would actually prefer LOOSE:
> INDISTINCT suggests (to me at least) that it is the opposite of DISTINCT
> (which it is not; it would even be acceptable to have the same behavior
> as DISTINCT).
> 
> > While the DISTINCT modifier ensures that duplicate solutions are
> > eliminated from the solution set, INDISTINCT simply permits them to be
> > eliminated. The cardinality of any set of variable bindings (solution)
> > in an INDISTINCT solution set at least one and not more than the
> 
> ...*is* at least one...

noted

> > cardinality of the solution set with no DISTINCT or INDISTINCT
> > modifier.
> 
> Perhaps better formulation would be to refer to the cardinality of the
> solution set as prescribed by the algebra.
> 
> > For example, the query
> > 
> >   PREFIX foaf:    <http://xmlns.com/foaf/0.1/>
> >   SELECT INDISTINCT ?name WHERE { ?x foaf:name ?name }
> > 
> > may have one, two (shown here) or three solutions:
> >   name
> >   "Alice"
> >   "Alice"
> 
> Of course, this only holds for a dataset which holds at least three
> solutions for Alice, you might want to make that more explicit in this
> paragraph (referring back to the example dataset explicitly?).

I think that in context with the DISTINCT proposal, it's clear. See
the attached HTML and tell me if you agree.
-- 
-eric

office: +1.617.258.5741 NE43-344, MIT, Cambridge, MA 02144 USA

(eric@w3.org)
Feel free to forward this message to any list for any purpose other than
email address distribution.



Received on Friday, 16 March 2007 19:40:49 GMT

This archive was generated by hypermail 2.3.1 : Tuesday, 26 March 2013 16:15:36 GMT