Semantic Web Overview

title

Semantic Web Overview

author

Lukasz Sokolowski

Exercises

RDFexamples

1. Family example
<!--
@prefix : <http://www.example.org/> .
:john    a           :Person .
:john    :hasMother  :susan .
:john    :hasFather  :richard .
:richard :hasBrother :luke .
-->

<rdf xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:mns="http://www.example.org/#">
	<mns:Person rdf:about="http://www.example.org/#john">
		 <mns:hasMother rdf:resource="http://www.example.org/#susan" />
		 <mns:hasFather>
			<rdf:Description rdf:about="http://www.example.org/#richard">
		 		<mns:hasBrother rdf:resource="http://www.example.org/#luke" />
			</rdf:Description>
		 </mns:hasFather>
	</mns:Person>
</rdf>




2. "Breeding" an aunt [-;

@prefix : <http://www.example.org/> .
:richard :hasSister :rebecca

{ ?a :hasFather ?b . ?b :hasSister ?c . } => { ?a :hasAunt ?c } .




3. Uncle is finally "cloned"! Rephrasing the paternity [=
 <!--
@prefix : <http://www.example.org/> .
:john    a           :Person .
:john    :hasMother  :susan .
:richard :hasBrother :luke .
:richard :isFather	 :john .
-->
Exercise:
	Define this ":john    :hasFather  :richard .", but in similar way to ":hasAunt".



	Define 'luke is an uncle to john'.




	Write rdf-schema for it.






4. SPARQL queries

My Apartment

@prefix ex: <http://example.org/> .
@prefix taubz: <http://razor.occams.info/index.html#> .
taubz:me            ex:own       taubz:my_apartment .
taubz:me            ex:own       taubz:my_computer .
taubz:my_apartment  ex:contains  taubz:my_computer .
taubz:my_apartment  ex:contains  taubz:friends_junk .
taubz:my_apartment  ex:location  <http://example.org/Philadelphia> .
taubz:me            ex:own       taubz:my_desk .
taubz:my_desk       ex:contains  taubz:my_pens_and_pencils .


Ex1 
Which resources are in my apartment?

?what
-----------------
taubz:my_computer
taubz:friends_junk

QUERY:

@prefix ex: <http://example.org/> .
@prefix taubz: <http://razor.occams.info/index.html#> .
select ?what 
where {
	taubz:my_apatement ex:contains ?what.
}


Ex2
Which resources are in my apartment?
Filter the results to contain only the resources that I own.









Ex3
Find resources contained in any object I own.









Ex3.1. Rewrite previous solution: pair ?container and ?what in select clause.