W3C home > Mailing lists > Public > www-rdf-interest@w3.org > August 2001

Re: anonymous nodes

From: David Allsopp <dallsopp@signal.dera.gov.uk>
Date: Tue, 14 Aug 2001 16:48:02 +0100
Message-ID: <3B794832.C6C2ED73@signal.dera.gov.uk>
CC: www-rdf-interest@w3.org


Seth Russell wrote:
> 
> From: <Patrick.Stickler@nokia.com>

> > IMO, anonymous nodes were a hack to allow collection structures as
> Objects,
> 
> Well maybe that is what some people use them for.   The primary reason,
> imho, is that we got so many nodes we can't name them all ....  tis
> impossible .... twill always be impossible.   But that doesn't mean that we
> can't start talking about things which are impossible to name or for which
> (in a distributed system) it is infeasible to name.  

Or just undesirable.  Some nodes are used as structural glue, so their
name is of no significance. We therefore don't want to have to give them
a name, since this requires the effort of generating a globally unique
name (which we can't achieve absolutely), so we don't accidentally clash
with someone else.  A locally unique name is easy, and we need that to
navigate arond the data graph, but we should dispose of it when passing
the data on to someone else, and they can assign their own locally
unique ID.

We don't want to waste names on things whose name is not important. The
more names we generate, the greater the probability of unintentional
clashes, especially when we get billions of triples floating around. 
Local names can safely be reused. And we'd have to waste bandwidth
sending billions of long machine-generated names around for no utility,
rather than just leaving gaps meaning "assign your own ID here".

Regards,

David Allsopp.

-- 
/d{def}def/u{dup}d[0 -185 u 0 300 u]concat/q 5e-3 d/m{mul}d/z{A u m B u
m}d/r{rlineto}d/X -2 q 1{d/Y -2 q 2{d/A 0 d/B 0 d 64 -1 1{/f exch d/B
A/A z sub X add d B 2 m m Y add d z add 4 gt{exit}if/f 64 d}for f 64 div
setgray X Y moveto 0 q neg u 0 0 q u 0 r r r r fill/Y}for/X}for showpage
Received on Tuesday, 14 August 2001 11:48:11 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:51:51 GMT