- From: Andy Seaborne <andy.seaborne@talis.com>
- Date: Thu, 29 Apr 2010 20:08:45 +0100
- To: Steve Harris <steve.harris@garlik.com>
- CC: SPARQL Working Group <public-rdf-dawg@w3.org>
On 26/04/2010 10:45 AM, Steve Harris wrote: > On 2010-04-25, at 18:11, Andy Seaborne wrote: >> * GROUP_CONCAT(?x,?y ; SEPARATOR=";") >> >> At F2F3, we converged on this named parameters form of GROUP_CONCAT. I suggested a uniform treatment with params available in custom aggregates. However, having tried this, I found it leads to complexity without obvious benefit. >> >> Question: >> Is this legal: >> GROUP_CONCAT(?x,?y ; SEPARATOR=?sep) >> where ?sep is some in-scope variable? For now, I've made the separator a fixed string depending clarification. > > I think constants only is a good idea. As I mentioned at the F2F, it otherwise raises a host of issues around grouped v's non-grouped values. I'm happy to leave it as a fixed string. > > As everything after the ; is passed directly to the set function, that expression must either be GROUP BY ?sep, or it would have to be SAMPLE(?sep), or similar, and I don't really want to go there. It could be made to work by requiring ?sep to be a variable in the group key (related to what is legal to project). Andy
Received on Thursday, 29 April 2010 19:09:21 UTC