- From: Holger Knublauch <holger@topquadrant.com>
- Date: Fri, 27 Feb 2015 08:57:34 +1000
- To: public-data-shapes-wg@w3.org
On 2/27/2015 5:28, Dimitris Kontokostas wrote: > Hi Richard, > > There are some cases with the current draft spec where counting is not > easy unless we require some conventions > e.g. for sections 15.1.1 CONSTRUCT-based Constraints [1] and 15.1.2 > ASK-based Constraints [2] how would you count the number of violations? > or when for a resource there are two violation values (sh:value) > should the values create separate violations or grouped in the same > resource? > > I already briefly pointed this to Holger. Yes thanks, and we should continue that discussion here on the public list. We need to look at specific example constraint definitions. I believe it should already be possible to rewrite any of the current SPARQL queries to repurpose their WHERE clause (e.g. you can use SELECT (?x AS ?value) to learn that ?x is the variable mapped to sh:value). Another idea is to let it run normally and then instantly post-process the newly created constraint violations, e.g. by grouping similar violations into one. Engines can do all this by themselves, but maybe we need some flag properties to make sure that certain aggregation of results is done on the fly. (Of course nothing hinders users to already create aggregations in their own WHERE clauses, so maybe what you need is already expressible and it becomes a matter of syntactic sugar). Anyway, in my role as an editor I very much welcome such suggestions and will put TODO snippets into the spec to make sure that open issues/suggestions are communicated properly. Holger
Received on Thursday, 26 February 2015 22:59:15 UTC