Re: Text about SPARQL-star built-in functions ready

On 04/03/2021 07:32, James Anderson wrote:
> olaf,
...

> 
> [that the count of requests to our service which specify application/n-quads as the content and/or accept media type outnumber by a factor of ten to one those which specify a triples variant notwithstanding, and despite that for well longer than recent memory, i have implemented nothing which concerned rdf statements for which the respective operands were typed as “triples", rather than “quads”, for the sake of discussion, this note will defer to the notion of “triples in graphs”.]
> 
> the concern is that the description of the operator should describe its application and results in adequate detail, that it not be necessary to comprehend its behaviour “by transitivity”.

Could you take a look at PR 114 and provide missing tests?

> for example, given a target dataset with some given number of graphs and an excerpt such as


> select (count(distinct ?t1) as ?t1Count)
>            (count(distinct ?t2) as ?t2Count)
>            (count(distinct ?t3) as ?t3Count)
>            (count(distinct ?t4) as ?t4Count)
> where {
>    graph ?g {
>      bind ( triple(_:id , dcam:memberOf, ?g) as ?t1)

Expressions can't have bnodes in them.
Did you mean BNODE("someFixedString")? BNODE()?

>      bind ( triple(:id , dcam:memberOf, ?g) as ?t2)
>      bind ( triple(_:id , dcam:memberOf, <>) as ?t3)
>      bind ( triple(:id , dcam:memberOf, <>) as ?t4)
>    }
> }
> 
> this reader would expect to be able to rely on the immediate text to unambiguously answer questions on the order of
> - is it permitted to apply that function in this manner?

?g is unbound in ?t2.

> - what values of the count variables result?

?t2Count = 0   BIND expression is unbound
?t4Count = 1   Constant expression; RDF (star) term-equality.

triple(BNODE("id") , dcam:memberOf, <>) => N for N graphs.
Unique BNODE per row => unique triple.

     Andy

> - were the select clause to be replaced with a construct clause which combined a graph with a triples template and targeted an initially empty dataset, how many triples would there be in the respective graphs if the construct clause specified a constant graph and how many if it specified the ?g variable?

I am unclear what the example is here.

> 
> best regards, from berlin,
> 
>

Received on Thursday, 4 March 2021 10:40:28 UTC