- From: Ivan Mikhailov <imikhailov@openlinksw.com>
- Date: Wed, 05 Dec 2007 07:25:59 +0600
- To: Andreas Langegger <al@jku.at>
- Cc: jena-dev@yahoogroups.com, public-rdf-dawg@w3.org
Hello, I've just committed a patch that lets aggregates be nested into result set expressions. As a side effect, select (count(*)) ... is now a valid syntax. sparql select ?s ?p (2 + max (bif:length(str(?o)))) where {?s ?p ?o . filter (isliteral (?o)) }; is now also valid query. Best Regards, Ivan Mikahilov OpenLink Software. > On 12/3/07, Andreas Langegger <al@jku.at> wrote: > Hello, > > it has already been noted that there are different syntax > styles > around for aggregate functions like COUNT which are out of > scope of > the SPARQL Rec: > https://www.blogger.com/comment.g?blogID=18002060&postID=4691605369637965896 > > In my case it's also an issue. The problem is, even if I just > use a > "SELECT COUNT(*)" without additional parentheses - which > should work > for both ARQ and Virtuoso (DBpedia e.g.) - ARQ will add the > ARQ-style > parentheses when serializing the Query back into a String: > "SELECT > (COUNT(*))" e.g. when executing remote queries... > > I'd like to here some comments and appraisal from the > community. Is > there a chance that aggregate functions become part of > official > SPARQL? When? ;-) > > A possible solution for ARQ would be to add a > Syntax.syntaxVirtuoso, > however this is not really a solution for this issue. > > Thanks, > Andy > > PS@ Andy Seaborne: > Concerning my remote-bug - it was my fault. However I was > already > confused enough cause I had another strange behavior with D2R > resulting in empty variable mappings when joining. Switched > off the > optimizer sinze I'm using some custom Transforms... now it's > working. > Thanks a lot and sorry for the false alarm! > > ---------------------------------------------------------- > Dipl.-Ing.(FH) Andreas Langegger > Institute for Applied Knowledge Processing > Johannes Kepler University Linz > A-4040 Linz, Altenberger Strafle 69 > http://www.faw.at > http://www.langegger.at >
Received on Wednesday, 5 December 2007 01:29:53 UTC