- From: Jorge Pérez <jperez@ing.puc.cl>
- Date: Tue, 5 Dec 2006 10:32:32 -0300 (CLST)
- To: "Jeen Broekstra" <jeen.broekstra@aduna-software.com>, "Andy Seaborne" <andy.seaborne@hp.com>
- Cc: public-rdf-dawg-comments@w3.org
Seaborne, Andy wrote: >Jeen Broekstra wrote: >> >> Defn: Diff >> >> At this point we got a bit lost. I have difficulties grokking why the >> definitions of Diff and LeftJoin include an expression as one of the >> operands. I can't even comment on how to rephrase this as I simply don't >> quite understand it (yet; I'll keep puzzling), but I would be much >> happier with a more 'standard' definition of both operators that just >> takes two operands, and then later on introduce the filter expression >> (if needed). >> >> At the very least I could use some clarification here :) > > http://lists.w3.org/Archives/Public/public-rdf-dawg/2006OctDec/0115.html > http://lists.w3.org/Archives/Public/public-rdf-dawg-comments/2006Oct/0030.html > http://lists.w3.org/Archives/Public/public-rdf-dawg-comments/2006Oct/0031.html > Only to state my point again: I think that the non-standard definition of Diff and LeftJoin having an expression as one of the arguments, only to provide users with a *one level* conditional OPT, is a bad design decision, and will raise a lot of problems in understanding and implementations in the future. How you explain users that they can make a *one level* conditional OPT and cannot make a *two level* conditional OPT? and cannot make somethig similar with other operators? http://lists.w3.org/Archives/Public/public-rdf-dawg-comments/2006Oct/0032.html - jorge
Received on Tuesday, 5 December 2006 13:32:53 UTC