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Re: Joseki, an RDF server. v1.0

From: Eric Jain <Eric.Jain@isb-sib.ch>
Date: Tue, 21 Jan 2003 14:15:39 +0100
Message-ID: <005101c2c14f$31686ea0$3ad721c0@caliente>
To: "Seaborne, Andy" <Andy_Seaborne@hplb.hpl.hp.com>
Cc: "rdf-interest" <www-rdf-interest@w3.org>

> Or was the
> subgraph of interest defined in some other way?

I'm interested in the complete subgraph, i.e. everything connected to <a> in
any way. Our data is such that any of these subgraphs can easily fit into
memory, though the complete data set is several gigabytes. Nevertheless,
dozens of queries would be necessary in order to retrieve each subgraph,
hence my interest in being able to get everything in one step.


> SELECT * WHERE (<a>, <hasItem>, ?b) (?b <hasValue> ?v)
> will get all depths of <hasItem> relationships.

So the combined results of

  SELECT * WHERE (<a>, ?x, ?b)

and

  SELECT * WHERE (<a>, ?x, ?b) (?b ?y ?v)

would contain everything connected to <a>?


> You can add a query languages yourself - all query processors are plugins.
> The website has an explaination of how to do this.

I'd rather not invent any new query languages, but I might have a look at
reducing the number of database calls, at least for my application (not sure
a generic solution is possible, you'd probably already have implemented it
:-).


--
Eric Jain
Received on Tuesday, 21 January 2003 08:15:40 GMT

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