Re: linked data mashups

2008/11/25 Juan Sequeda <juanfederico@gmail.com>

>
>
>> How does SQIUN differ to a typical HTTP SPARQL endpoint? So far it accepts
>> a "query" parameter as a SPARQL select statement and executes the parameter
>> on (some configured?) SPARQL endpoints from looking at the single sourcefile
>> I could find [1]. Having said that, I have been holding off getting my
>> bio2rdf server to actually process rdf but it doesn't look so hard now. (The
>> bio2rdf server is actually more generic than just biology or even bio2rdf
>> but it is still named that in response to its origins. And in contrast to
>> SQUIN it focuses on CONSTRUCT queries rather than SELECT)
>>
>>
> SQUIN is based on the Semantic Web Client Library[1]. "The *Sematic Web
> Client Library* represents the complete Semantic Web as a single RDF
> graph. The library enables applications to query this global graph using
> SPARQL- and find(SPO) queries. To answer queries, the library dynamically
> retrieves information from the Semantic Web by dereferencing HTTP URIs, by
> following rdfs:seeAlso links, and by querying the Sindice<http://sindice.com/>search engine. The library is written in Java and is based on the Jena
> framework."
>
> Now just imagine the Semantic Web Client library on your server, next to
> the rest of the LAMP stack. Your server is the sparql endpoint for the whole
> Semantic Web. No need of querying individual sparql endpoints. This is SQUIN
>
> [1] http://www4.wiwiss.fu-berlin.de/bizer/ng4j/semwebclient/
>

Rightio, that sounds promising.

I have taken the idea that there are a number of SPARQL endpoints available
and no easy way of querying across them and masked over the endpoints using
the Bio2RDF URI syntax, although any URI syntax can be used as long as it
follows the idea that databases can be represented as namespaces and that
they have identifiers. Unfortunately I haven't got Sindice integrated yet...
Must get around to doing that.

I wrote something in .NET using the SemWeb library that basically does what
you are trying to do but I never released it because it ended up being
pretty slow and not as useful as focusing on the dereferencing ability that
you kind of assume is going to be available.

Cheers,

Peter