- From: Peter F. Patel-Schneider <pfpschneider@gmail.com>
- Date: Thu, 7 Jul 2016 06:42:32 -0700
- To: james anderson <james@dydra.com>, public-sparql-exists@w3.org
On 07/07/2016 06:31 AM, james anderson wrote: > good afternoon; > >> On 2016-07-07, at 14:12, Peter F. Patel-Schneider <pfpschneider@gmail.com >> <mailto:pfpschneider@gmail.com>> wrote: >> >> >> >> […] >> I think that Andy's solution is acceptable as a starting point. >> >> It might have been better to have had ToMultiSet in the Graph Pattern column >> of the table, but even though ToMultiSet is not really a solution modifier and >> thus should be in the Graph Pattern column. However, most errata should be >> about making the smallest change required to fix a problem, and Andy's >> suggested errata does this. >> >> However, Andy's suggested errata is not sufficient because multisets also need >> to be allowed as Graph Patterns. Multisets show up in the SPARQL algebra as >> the translation on inline data and thus need to be accommodated as well. >> >> >> So I suggest >> >> Draft: >> >> [[ >> query-errata-N: >> >> "Section 18.2 Translation to the SPARQL Algebra" intro (end): >> >> ToMultiSet can be used where a graph pattern is mentioned below because the >> outcome of evaluating a graph pattern is a multiset. >> >> Multisets of solution mappings are elements of the SPARQL algebra. Multisets >> of solution mappings count as graph patterns. >> ]] >> >> >> I note that this problem does not just affect EXISTS, but affects just about >> every construct because of the wording >> >> P, P1, P2 : graph patterns >> >> near the beginning of 18.6. >> >> peter >> >> PS: I do note that the translation to the SPARQL algebra is defined in a >> somewhat sloppy manner that makes it hard to determine exactly what is >> supposed to result. I don't think that there are any problems that arise from >> this sloppiness but the translation needs some attention if there ever is a >> next version of SPARQL. >> > > -1 > > what is the concrete benefit of the “add a note” approach, when not putting > the entry in the table puts the reader in the position to need to correlate > information at different locations in the document? > > best regards, from berlin, > --- > james anderson | james@dydra.com <mailto:james@dydra.com> | http://dydra.com The only benefit is that this is a smaller change. It does not remove ToMultiSet from the solution modifiers part of the algebra. I don't think that there are any negative consequences of the removal. I believe that moving ToMultiSet results in a better document. However, the SPARQL document is long and complex so I'm not completely sure of the lack of negative consequences, thus I prefer the smaller change because I see only a tiny added benefit from making the larger change. peter
Received on Thursday, 7 July 2016 13:48:29 UTC