- From: Axel Polleres <axel.polleres@deri.org>
- Date: Mon, 14 Feb 2011 10:59:32 +0000
- To: "Steve Harris" <steve.harris@garlik.com>
- Cc: "Andy Seaborne" <andy.seaborne@epimorphics.com>, "SPARQL Working Group" <public-rdf-dawg@w3.org>
Related to the issue of ORDER in GROUP_CONCAT we had a mail thread starting at http://lists.w3.org/Archives/Public/public-rdf-dawg/2010OctDec/0041.html and ending at http://lists.w3.org/Archives/Public/public-rdf-dawg-comments/2010Oct/0001.html ... this was then discussed in the TC on 2010-10-26: http://www.w3.org/2009/sparql/meeting/2010-10-26#line0100 there we had a strawpoll on whether or not we want an order feature in GROUP_CONCAT... Options for group_concat: 1) no order_by 2) simple order_by 3) full ordering by expressions (e.g. order by second letter of a word, etc.) where a clear majority voted for 1), mainly because of concerns that anything else would not be doable with the remaining time/resources. As far as I understand, what is now being discussed is 3), correct? Back in october, no one voted for 3). Unless someone thinks we have substantial new information, I think we should stick with this position. BTW: I just see that, on IRC, in that TC, Steve suggested to make a postponed issue out of it: http://www.w3.org/2009/sparql/meeting/2010-10-26#line0133 but so far we haven't added it as an issue. best, Axel On 14 Feb 2011, at 10:33, Steve Harris wrote: > On 2011-02-14, at 09:34, Andy Seaborne wrote: > > > > On 14/02/11 09:17, Axel Polleres wrote: > >> Hi steve, > >> > >> On 8 Feb 2011, at 16:31, Steve Harris wrote: > >> > > ... > >> > >>> He raises a reasonable point about the interaction of ORDER BY, > >>> http://www.w3.org/2009/sparql/docs/query-1.1/rq25.xml#convertSolMod > >>> could be construed as meaning that ORDER is preserved in aggregate > >>> operations, though the algebra does say it's operations on > >>> multisets. > >> > >> Is this something that needs to be discussed? Could an alternative > >> behaviour to the current one be achieved with reasonable effort and > >> the time/resources we still have? > > > > This relates to Jeen's point about GROUP_CONCAT and ORDER BY > > > > http://lists.w3.org/Archives/Public/public-rdf-dawg-comments/2011Feb/0004.html > > > > Maybe we should add "; ORDER BY" to GROUP_CONCAT. > > ; ORDER BY (and ; LIMIT) would be very useful, but on the other hand, I'm thinking that aggregates are quite complex as it is. > > - 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 > >
Received on Monday, 14 February 2011 11:01:08 UTC