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Re: What Happened to the Semantic Web?

From: Sean B. Palmer <sean@miscoranda.com>
Date: Fri, 13 Oct 2017 10:07:29 +0100
Message-ID: <CAH3-oEeyLJm6dZSi=j-9Yo-18gU0gxjA7J8Rf2zpONq=WigDUQ@mail.gmail.com>
To: Martynas Jusevičius <martynas@atomgraph.com>
Cc: SW-forum Web <semantic-web@w3.org>, public-lod <public-lod@w3.org>, www-archive <www-archive@w3.org>
Compare these syntaxes:

<> select { Result is (?a ?b) };
   where  { ?a <http://somewhere/pred1> ?b.
            ?b math:lessThan 5}.

SELECT ?a ?b
WHERE { ?a <http://somewhere/pred1> ?b.
        FILTER (?b < 5) }

[ a sp:Select;
    sp:resultVariables (_:a _:b);
    sp:where ([ sp:subject _:a;
                sp:predicate <http://somewhere/pred1>;
                sp:object _:b ]
              [ a sp:Filter;
                sp:expression
                  [ sp:arg1 _:b;
                    sp:arg2 5;
                    a sp:lt ] ])
].

N3QL and SPIN are both homoiconic RDF representations, but N3QL is
almost as concise as SPARQL whereas SPIN is not. If you're only used
to SPIN, then no wonder you thought that this idea is "like expecting
SQL queries to be expressed as tables". The main difference is that
N3QL supports formulae, like named graphs, that eliminate the need for
reification.

I say that SPARQL is not RDF based because, unlike the N3QL and SPIN
representations above, the SPARQL representation is not an RDF format.
You can't say how many triples are in the second example above,
whereas you can for the first and third.

Not being RDF based means that you have to write a new parser for
SPARQL, whereas for SPIN and N3QL we can use existing ones. The
further advantage of N3QL is that we can use existing logic machines
such as CWM and Euler to do the querying too! In any case, all of this
functionality has now been duplicated (worse) as SPARQL, but at the
time it would have been a major saving and would have fit in better
with the contemporary Semantic Web toolset.

https://www.w3.org/2000/10/swap/doc/cwm.html
http://eulersharp.sourceforge.net/
https://www.w3.org/DesignIssues/N3Logic

These references may help to introduce you to an important side of the
Semantic Web that has apparently been forgotten by some of its current
developers.

-- 
Sean B. Palmer, http://inamidst.com/sbp/
Received on Friday, 13 October 2017 09:08:12 UTC

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