
An Introduction to the Resource Description Framework (1998) - tosh
https://www.dlib.org/dlib/may98/miller/05miller.html
======
emmanueloga_
TL; DR

I think Jena, a free and open source RDF framework, has been around for the
last 20 years, and still releases pretty often. If you are considering using a
graph database for your next project, you should give it a try! Here are some
notes on how to get into RDF [1].

\--

RDF is really at its core such a simple concept! What's built on top can go
pretty deep though. RDF is a technology to describe graphs, with tools on top
that allow querying, traversing, validating, and inferring information.

The way RDF describes graphs is with the use of a "triple". This triple has
the form:

Subject -> Property -> Object

A sample triple could be: Tarantino Directed Kill-Bill.

The power of the model comes from the fact the elements of the triple use
unique IDs by mean of URIs, so a more realistic triple could be:

<[http://imdb.com/tt0266697>](http://imdb.com/tt0266697>)
<[http://movies.com/job/director>](http://movies.com/job/director>) "Kill Bill
Vol. 1"@en.

In this example, the object is a literal instead of a entity with its own URI:
the English title of a movie. As long as someone else uses the same subject
URI, I may automatically discover new things about my own data by merging
someone else triples into mine. There's also an extension that allows naming
the graph where the triple lives: the triple becomes a "quad". The name of the
graph should be an URI: <[https://me.com/my-movies>](https://me.com/my-
movies>).

Through the years there's been more stuff built on top of the model: various
serialization formats (most of them plain text based), a query language
(SPARQL, similarities with Datalog), frameworks for "semantic inference"
(OWL), schemata and constraints, asking the graph to be a certain shape (SPIN,
SHEX, SHACL), an easy way to make statements about the triples, like "this
triple was created on this date by this person" (RDF*), and I'm sure a lot
more stuff I'm forgetting or I don't know about :-).

1:
[https://www.reddit.com/r/semanticweb/comments/fxtaxe/books_o...](https://www.reddit.com/r/semanticweb/comments/fxtaxe/books_on_the_semantic_web/fppxi1l/)

~~~
jbmsf
At my last company, the system that eventually became our Knowledge Graph
started out as RDF. It seemed like a great fit, but we didn't really have much
luck. There was an unnecessarily complicated process for schema definition and
the SPARQL engine we chose (on top of PostgreSQL) wasn't ready for a
production load (e.g. was not performant).

I really liked the concept and we borrowed the "triple" approach in our next
iterations, but we really didn't get any benefit from using RDF.

Quite possible it was our fault.

~~~
sawaruna
What did you end up moving to?

------
jaygray0919
Most websites in the world implement RDF in the form of schema.org - a nearly
pure implementation of RDF (pure meaning no non-standard variants).

Wikidata is an RDF instance.

The largest chemical database in the world is based on RDF (PubChem).

There are hundred, thousands of other RDF instances.

------
sawaruna
As someone still using RDF in research / work, always nice to see it pop up on
HN. Even if it is nothing particularly substantial.

~~~
OnlyOneCannolo
Can you share something more substantial with us? How are you using RDF? Can
you share some other RDF resources? Do you have an uncommon take on RDF?

~~~
sawaruna
I wouldn't say I have an uncommon take on RDF. I feel it gets more focus
(maybe too much) in semantic web related academia and research than it does on
the general web. And the substantial thing wasn't meant to be that harsh of a
critique, but like another comment mentioned, sometimes these 'introduction /
wiki articles about __' are a bit of a tease, and I wish someone were posting
something more novel.

As for what I'm doing, it's a project that is taking various siloed fan-
created data on the web and collecting, aggregating, and transforming it into
RDF for the purpose of being queried by researchers. I think RDF and RDF-
adjacent things (e.g. knowledge organization, ontology application) are useful
here, but the actual querying / data analysis requiring an RDF transformation
is maybe questionable.

------
DLA
Why do people post wikipedia links with absolutely no context or comment?

~~~
JadeNB
I often find Wikipedia-only links handy to introduce me to topics that I never
even knew existed—that is, where, in some sense, "this topic exists" is
interesting in itself.

One particularly memorable one was
[https://en.wikipedia.org/wiki/199_398_500_A](https://en.wikipedia.org/wiki/199_398_500_A)
(though I can no longer find the HN link to it); it's then easy enough for me
to Google around for more context if I care to do so.

~~~
tosh
[https://news.ycombinator.com/item?id=23011467](https://news.ycombinator.com/item?id=23011467)

