- From: Steve Harris <steve.harris@garlik.com>
- Date: Fri, 11 Feb 2011 15:16:46 +0000
- To: Matthew Perry <matthew.perry@oracle.com>
- Cc: SPARQL Working Group <public-rdf-dawg@w3.org>
I should add - the intention is to leave the results for existing set functions exactly the same, but to change their signatures. - Steve On 2011-02-11, at 15:09, Steve Harris wrote: > It does as written, but that's an unintended consequence, the def'n of Count() will need to be change to not count error values. > > - Steve > > On 2011-02-11, at 14:00, Matthew Perry wrote: > >> Hi Steve, >> >> Lets say M = (1, 2, 3, "a", "b") >> >> Does this change COUNT(xsd:int(?x)) from 3 to 5? >> >> - Matt >> >> On 2/11/2011 7:03 AM, Steve Harris wrote: >>> I've spoken with Andy on IRC, and he also agrees that it's probably better without it, so the current draft of rq25 doesn't have the error count argument. >>> >>> Following some discussion on IRC last night, I've also clarified the return types of the set functions. >>> >>> - Steve >>> >>> On 2011-02-11, at 10:55, Steve Harris wrote: >>> >>>> Hi all, >>>> >>>> Currently the Set Functions in Aggregates (ie. the underlying functions) are defined like: >>>> >>>> Func(M, errors, scalars) >>>> >>>> where M a multiset of the values from the group, e.g. if you have SUM(?x) and ?x is 1,2,3 in the group, then M = (1,2,3). But M is defined used ListEvalE(), so all the results which are errors are removed from the multiset. >>>> >>>> errors is a count of the errors (which where removed from M). >>>> >>>> I think it would be much simpler if instead M included the errors, and the error count argument was dropped, then it would be: >>>> >>>> M = ListEval(exprlist, range(g)) >>>> >>>> func(M, scalarvals), for non-DISTINCT >>>> func(Distinct(M), scalarvals), for DISTINCT >>>> >>>> Dave B also complained about the error count argument saying it was redundant in his comment. >>>> >>>> I don't quite remember why it was included? I think Andy S might have suggested it, something about future extensibility? But I don't see what function it performs. >>>> >>>> So, my question is, can anyone think of a good reason to keep it? >>>> >>>> - Steve >>>> >>>> -- >>>> Steve Harris, CTO, Garlik Limited >>>> 1-3 Halford Road, Richmond, TW10 6AW, UK >>>> +44 20 8439 8203 http://www.garlik.com/ >>>> Registered in England and Wales 535 7233 VAT # 849 0517 11 >>>> Registered office: Thames House, Portsmouth Road, Esher, Surrey, KT10 9AD >>>> >>>> >> > > -- > Steve Harris, CTO, Garlik Limited > 1-3 Halford Road, Richmond, TW10 6AW, UK > +44 20 8439 8203 http://www.garlik.com/ > Registered in England and Wales 535 7233 VAT # 849 0517 11 > Registered office: Thames House, Portsmouth Road, Esher, Surrey, KT10 9AD > > -- Steve Harris, CTO, Garlik Limited 1-3 Halford Road, Richmond, TW10 6AW, UK +44 20 8439 8203 http://www.garlik.com/ Registered in England and Wales 535 7233 VAT # 849 0517 11 Registered office: Thames House, Portsmouth Road, Esher, Surrey, KT10 9AD
Received on Friday, 11 February 2011 15:17:20 UTC