- From: Steve Harris <steve.harris@garlik.com>
- Date: Thu, 7 Oct 2010 11:18:35 +0100
- To: Axel Polleres <axel.polleres@deri.org>
- Cc: SPARQL Working Group <public-rdf-dawg@w3.org>
My feeling is that you need ORDER BY expression to make it useful.
- Steve
On 2010-10-07, at 02:50, Axel Polleres wrote:
> When thinking about practical examples for GROUP_CONCAT, I can hardly think of any where I wouldn't want to impose an order...
> ... thus, what's the opinions about adding another scalar parameter "order" which takes as parameter "DESC"|"ASC"
>
> That is, e.g. something like:
>
> PREFIX foaf: <http://xmlns.com/foaf/0.1/>
> SELECT ( SAMPLE(?N) as ?Name)
> ( GROUP_CONCAT(?M; SEPARATOR = ", " , ORDER="ASC") AS ?Nicknames )
> WHERE { ?P a foaf:Person ;
> foaf:name ?N ;
> foaf:nick ?M . }
> GROUP BY ?P
>
> It seems that GROUP_CONCAT in SQL dialects also has an ORDER BY clause, as e.g. a quick google search reveals for MySQL [1].
>
> Steve, do you think that would be a big deal to add?
> Others?
>
> Axel
>
> P.S.: I thought briefly about not only allowing "ASC"|"DESC" but an arbitrary ORDER BY expression, however, that admittedly seems not
> to go well with the current Aggregation() semantics definition, I am afraid...
>
>
> 1. http://dev.mysql.com/doc/refman/5.0/en/group-by-functions.html#function_group-concat
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Received on Thursday, 7 October 2010 10:19:09 UTC