- From: Andy Seaborne <andy.seaborne@epimorphics.com>
- Date: Wed, 06 Oct 2010 09:12:23 +0100
- To: Axel Polleres <axel.polleres@deri.org>
- CC: SPARQL Working Group <public-rdf-dawg@w3.org>
On 05/10/10 20:13, Axel Polleres wrote:
> looking over the minutes from last time and trying to understand the conclusion of the BINDINGS discussion...
>
> Do I miss anything or is semantically just the same as a Subquery:
>
> i.e.
>
> WHERE { P ]
> BINDINGS ?X1 ... ?Xn { ( c11 ... c1n ) (c21 ... c2n) ... }
>
>
> just boils down to
>
>
> WHERE { { P }
> { {SELECT ( c11 AS ?X2 ) ... ( c1n AS ?Xn ) WHERE {} }
> UNION
> {SELECT ( c21 AS ?X2 ) ... ( c2n AS ?Xn ) WHERE {} }
> UNION
> ...
> } }
Sort of. That syntax translation needs to put the constants inside
WHERE clause and needs tweaking to cope with UNDEF. The subquery
SELECT-UNION-WHERE-{} can be used to insert constants but breaks the
streaming possibilities given by BINDINGS which present query, then
variables then the data.
Andy
Received on Wednesday, 6 October 2010 08:13:00 UTC