- From: Andy Seaborne <andy.seaborne@epimorphics.com>
- Date: Wed, 01 Feb 2012 13:58:04 +0000
- To: public-rdf-wg@w3.org
On 01/02/12 13:40, David Wood wrote:
>>>> >>> <s> <p> {<a> <b> <c> }
>>>> >>>
>>>> >>> you mint an identifier (<g1> ) then store these quads:
>>>> >>>
>>>> >>> <s> <p> <g1> DEFAULT
>>>> >>> <a> <b> <c> <g1>
>>> >>
>>> >>
>>> >> For what it is worth, this is what Mulgara does.
>> >
>> > David,
>> >
>> > Does Mulgara claim to support graph literals?
> Mulgara supports what it calls named graphs. In fact, you*can't* query Mulgara (or its predecessors) without querying a particular graph. Our original query language (TQL) forced you to name a graph; the SPARQL implementation defaults to the default graph as configured, I believe. Each quad is indexed with its graph membership.
>
> There are some "special" graphs in Mulgara, especially the "system" graph that stores triples about all the graphs that the system holds. They are exposed and queryable.
>
>> >
>> > What does
>> >
>> > SELECT ?o {<s> <p> ?o }
>> >
>> > return?
> If you queried the system graph thusly you would get the list of graph URIs held by that Mulgara instance.
Query the configured default graph.
Does ?o return {<a> <b> <c> } or <g1> or something else?
(By the way - is the data syntax for graph literals understood by
Mulgara documented anywhere?)
Andy
Received on Wednesday, 1 February 2012 13:58:31 UTC