sparql tutorial ii & iii

SPARQL TUTORIALSPARQL TUTORIALBY AMNA BASHARAT

7thOctober , 2008FAST‐NU , Islamabad

in a nutshellin a nutshellin a nutshellin a nutshell

Adapted from fabien, gandon, inria

RDF triple model is the first layer of the is the first layer of the semantic web standards

FAST – NU, Islamabad, Fall 2008

SPARQL on top...an RDF query language an RDF query language and data access protocol


SPARQLstands forSPARQL Protocol and SPARQL Protocol and RDF Query Language


SPARQL in 3 partspart 1: query languagepart 1: query languagepart 2: result format


part 3: access protocol

SPARQL querySELECTSELECT ...FROM ...


WHERE { ... }

SELECT clause

to identify the values to to identify the values to be returned


FROM clause

to identify the data to identify the data sources to query


q y

WHERE clause

the triple/graph pattern the triple/graph pattern to be matched against the


gtriples/graphs of RDF

WHEREclauseWHEREclausea conjunction of triples: {?x rdf:type ex:Person?x ex:name ?name }}


PREFIX

to declare the schema to declare the schema used in the query


q y

example : persons and their names

PREFIX ex: <http://inria.fr/schema#>SELECT ?person ?nameWHERE {WHERE {?person rdf:type ex:Person?person ex:name ?name?person ex:name ?name .}


Example or Result

<?xml version="1.0"?> <sparql xmlns="http://www.w3.org/2005/sparql-results#" ><head><variable name="person"/>

<variable name="name"/> </head><results ordered="false" distinct="false"><results ordered="false" distinct="false"><result><binding name="person">

<uri>http://inria.fr/schema#fg</uri>

</binding>

<binding name="name">

<literal>gandon</literal><literal>gandon</literal>

</binding></result>

<result>


<result> ...

FILTER

to add constraints to the to add constraints to the graph pattern (e.g.,


g p p ( g ,numerical like X>17 )

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Example: persons at least 18‐year old

PREFIX ex: <http://inria fr/schema#>PREFIX ex: <http://inria.fr/schema#>SELECT ?person ?nameWHERE {?person rdf:type ex:Person?person ex:name ?name .

?person ex:age ?age .

FILTER (?age > 17)FILTER (?age > 17)}

FAST – NU, Islamabad, Fall 2008 16

FILTER can use many operators functions (e g operators, functions (e.g., regular expressions), and


even users' extensions17

OPTIONAL

to make the matching of a to make the matching of a part of the pattern


p poptional

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Example:: retrieve the age if available

PREFIX e <htt //i i f / h #>PREFIX ex: <http://inria.fr/schema#>SELECT ?person ?name ?ageWHERE {WHERE {?person rdf:type ex:Person?person ex:name ?name .

OPTIONAL { ?person ex:age ?age }} }


UNION

to give alternative to give alternative patterns in a query


p q y

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Example: explicit or implicit adults

PREFIX ex: <http://inria.fr/schema#>SELECT ?nameWHERE {WHERE {?person ex:name ?name .

{{ ?person rdf:type ex:Adult }UNION{ ?person ex:age ?age{ ?person ex:age ?age FILTER (?age > 17) }

}}


}

Sequence & modify

ORDER BY to sortORDER BY to sortLIMIT result number


OFFSET rank of first result22

Example: results 21 to 40 ordered by name

PREFIX ex: <http://inria.fr/schema#>SELECT ?person ?nameWHERE {?person rdf:type ex:Person?person ex:name ?name .}

ORDER BY ?nameLIMIT 20OFFSET 20


UNBOUND

test a variable is not bound ; test a variable is not bound ; used for negation as failure


Example: persons who are not known authors

PREFIX <htt //i i f / h #>PREFIX ex: <http://inria.fr/schema#>SELECT ?nameWHERE {?person ex:name ?name .

OPTIONAL { ?person ex:author ?x } ! b d( )FILTER ( ! bound(?x))

}


NEGATION

is tricky and errors can easily be made.

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PREFIX ex: <http://inria.fr/schema#>SELECT ?nameWHERE {WHERE {?person ex:name ?name .

?person ex:knows ?x?person ex:knows ?x FILTER ( ?x != "Java" )}

FAST – NU, Islamabad, Fall 2008? does this find persons who do not know "java" ?

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NO! also persons who know something else !

PREFIX ex: <http://inria.fr/schema#>SELECT ?nameWHERE {?person ex:name ?name .

?person ex:knows ?x FILTER ( ?x != "Java" )}

Amna ex:knows "Java"

Amna ex:knows "C++"


Amna is a answer...

YES! persons who are not known to know "java" ... negation of an option...

PREFIX ex: <http://inria.fr/schema#>SELECT ?nameWHERE {?person ex:name ?name .

OPTIONAL { ?person ex:knows ?x

FILTER ( ?x = "Java" ) } !FILTER ( ! bound(?x) )

}


ASK

to check just if there is at to check just if there is at least one answer ; result is


;"true" or "false"

Example: is there a person older than 17 ?

PREFIX ex: <http://inria.fr/schema#>ASK

{?person ex:age ?age FILTER (? > 17)FILTER (?age > 17) }


CONSTRUCT

return a specific RDF return a specific RDF graph for each result


g p

Example: return instances of adults for persons older than 17

PREFIX ex: <http://inria.fr/schema#>CONSTRUCTCONSTRUCT

{

?person rdf:type ex:Adult

}

WHERE

{?person ex:age ?age FILTER (?age > 17) }


}

SPARQL protocol

sending queries and their sending queries and their results accross the web


Example: with HTTP Binding

GET /sparql/?query=<encoded query>HTTP/1.1

Host: www.inria.fr

User-agent: my-sparql-client/0.1


Example: with SOAP Binding

<?xml version="1.0" encoding="UTF-8"?>

<soapenv:Envelopexmlns:soapenv="http://www.w3.org/2003/05/soap-envelope/"

xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

<soapenv:Body>

<query-request xmlns="http://www.w3.org/2005/09/sparql-<query request xmlns http://www.w3.org/2005/09/sparqlprotocol-types/#">

<query>SELECT ?x ?p ?y WHERE {?x ?p ?y}</query>

/</query-request>

</soapenv:Body>

</soapenv:Envelope>


/ p p

SPARQL as a Protocol

A way of communication between parties th t SPARQL ithat run SPARQL queries.Defining a way of invoking the service. Bindings of a transport protocol for that goal.


SPARQL Protocol (1)

WSDL description file:i i f h lDescription of the protocol.

Not for human understanding.

bi diHTTP binding:Specify how to encode SPARQL queries in URLs ith GET d POST th d with GET and POST methods.

SOAP binding:S if h SOAP f Specify the SOAP message format (XML message exchange format for queries)


WSDL Description file

WSDL description file: (HTTP binding part)bi di " Htt " <binding name="queryHttp" interface="tns:SparqlQuery“ >… >

<fault name="MalformedQuery" whttp:zode="400"/> <!‐‐ the GET binding for query operation ‐‐><!‐‐ the GET binding for query operation ‐‐><operation ref="tns:query" whttp:method="GET" whttp:inputSerialization=“ " />whttp:inputSerialization= … />

</binding>


SPARQL Protocol (2)

Interface SparqlQueryl iOnly one operation: query

For transferring string query

D t t i XML hData types: via XML schemaBindings: HTTP / SOAP binding for invokable operationsoperations.

A service must support SparqlQuery interfaceinterface

support the bindings as described in the WSDL.


SPARQL Protocol Examples

Examples after we cover SPARQL Query L f RDFLanguage for RDF.


SPARQL Query Language

A standard query language in the form of i i t th RDF d t expressive query against the RDF data

model…D t lData access languageGraph patternsPowerful than XML queries in some aspects


SPARQL Query Language (1)

SQL:SQL:Internals of DB (tables, fields, data, meaning)Impossible to query databases on the Impossible to query databases on the WILDWILDWEB.

So what does SPARQL propose?So, what does SPARQL propose?URIs.Querying databases globallyQuerying databases globally.Combining data globally.Value of data grows exponentially with the ways


Value of data grows exponentially with the ways you combine it.

The Wild Wild Web

SQL SPARQLSQL SPARQLXML


SPARQL Query Language (2)

Data structure definitions are being d l d ld id i di t ib t d developed worldwide in a distributed manner.C t l i (D bli C F f Common ontologies (Dublin Core, Foaf, DOAP, etc.)A d b bli h h l i i A database publishes the ontologies it exports toAn application queries it using those ontologies.


Power of SPARQL Illustrated

Ask fotograf.com if it has a picture which t h t i t h titl matches some constraints such as title,

date, size, and some other tag…Th k l f URL i l ti t th Then ask google for URLs in relation to the tag we specified.A d h l f h And turn the results of these two uncoordinated data as an RSS feed on your sitesite.All this in just two‐three SPARQL queries.


Power of SPARQL (2)

Ask music cds of price less than 10You can run this query against hepsiburada.com, amazon, e‐bay, itti idi th ll th gittigidiyor.com or any other seller on earth

who has a website and a database.N ll d h h i d bNo seller needs to change their databases.Seller needs: Conversion layer between ontologies and database.Client needs: connectivity framework (like


JDBC) for java.47

Power of SPARQL (2) Imp.

PREFIX dc: htt // l /d / l t / / PREFIX <http://purl.org/dc/elements/1.1/> PREFIX

ns: <http://example.org/ns#>SELECT ?titl ? i SELECT ?title ?price WHERE {

?x ns:price ?price ?x ns:price ?price .FILTER (?price < 10) . ?x dc:title ?title ?x dc:title ?title . }


SPARQL Syntax ‐brief‐1

URIsi<URI> in < >

or@PREFIX prefix: <http://....>fi f f ll URIprefix:name for full URI

Literals“Literal“ or “Literal”@language

Blank Node_:name or [ ] for a Blank Node used just once


SPARQL Syntax ‐brief‐2

Triples and .:x :y :z . :t :q :s .

Common predicate and subject::x :y :z, :t .which is the same as :x :y :z . :x :y :t .

Common subject:RDF Collections

:x :y ( :z :t :q :s )which is short for many triples (as lists in LISP)


A walkthrough example illustrating the power of SPARQL

XML/SQL SPARQL


Walkthrough example (1xml)

<Person><name>Henry Story</name><mbox>[email protected]</mbox><knows>

<Person>i<name>Tim Bray</name>

<mbox>[email protected]</mbox>

</Person><Person>

<name>Jonathan Story</name> <mbox>[email protected]</mbox>

</Person> </knows>

</Person>


Walkthrough example (1sparql)

[ a :Person; :name "Henry Story"; :mbox <mailto:[email protected]>;

:knows [ a :Person; :name "Tim Bray";

b il b@ ] :mbox <mailto:[email protected] ]; :knows [ a :Person;

name "Jonathan Stor " :name "Jonathan Story"; :mbox <mailto:[email protected]> ];

]


] .

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Graph representation


Walkthrough example (2)

<AddressBook><Person>

<name>Jonathan Story</name> <name>Jonathan Story</name> <mbox>[email protected]</mbox><address>

<Country>France</Country></address>

</Person> <Person> <Person>

<name>Tim Bray</name> <mbox>[email protected]</mbox>

dd<address><Country>Canada</Country>

</address>


</Person></AddressBook>


[ a :Person;

:name "Tim Bray"; :name "Tim Bray";

:mbox <mailto:[email protected]>

:address [ a :Address; :address [ a :Address;

:country "Canada"@en ] ].

[ a :Person; [ ;

:name "Jonathan Story";

:mbox <mailto:[email protected]> :address [

a :Address;


:country "France"@en ]

]. 56

Graph representation



These graphs can be merged into the f ll i h i ll if th b following graph especially if the mbox relation is stated as being inverse functional


Graph representation(merged)



"Who does Henry know who lives in Canada, d h t i th i il dd ?" and what is their e‐mail address?"

Can only be answered by aggregating data f b th d t from both documents. Can not be done using the XML query l hi h l k h languages, which can only work on the surface of the document.



SELECT ?name ?mail WHERE {

[a :Person; :name "Henry Story"; :knows [ :name ?name; [ ;

:mbox ?mail; :address [ a :Address;:address [ a :Address;

:country "Canada"@en; ] ] ]


] ] ].}

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Names and websites of contributors to Pl tRDFPlanetRDF

PREFIX foaf: <http://xmlns.com/foaf/0.1/> SELECT ? ? b it SELECT ?name ?website FROM <http://planetrdf.com/bloggers.rdf> WHERE { WHERE {

?person foaf:weblog ?website ;foaf:name ?name .

?website a foaf:Document }


Protocol Example (1)

PREFIX foaf: <http://xmlns.com/foaf/0.1/>PREFIX dc: <http://purl.org/dc/elements/1.1/>SELECT ?who ?g ?mboxFROM <http://my.example/publishers>FROM NAMED <http://my.example/alice>p // y p /FROM NAMED <http://my.example/bob>WHERE { WHERE { ?g dc:publisher ?who . GRAPH ? { ? f f b ? b } }


GRAPH ?g { ?x foaf:mbox ?mbox } }

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Protocol Example (1)

HTTP/1.1 200 OKd 8 GDate: Wed, 27 Dec 2005 12:48:25 GMT

Server: Apache/1.3.29 (Unix) PHP/4.3.4 DAV/1.0.3Connection: closeContent‐Type:

application/sparql‐results+xml; charset=utf‐8l i<?xml version="1.0"?>

<sparql xmlns=“…">… …</sparql>


References

http://www.w3.org/2004/Talks/17Dec‐l/i t / ll ht lsparql/intro/all.html

http://jena.sourceforge.net/ARQ/Tutorial/http://blogs.sun.com/roller/page/bblfishhttp://xmlarmyknife.org/api/rdf/sparqlhttp://xml.com/lpt/a/2005/11/16/introducing‐sparql‐querying‐semantic‐web‐tutorial.htmlhttp://www.w3.org/2005/Talks/12May‐


p 3 g 5 ySPARQL/all.html

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References (2)

http://www‐8 ib /d l k / l/lib /j128.ibm.com/developerworks/xml/library/j‐

sparql/htt // /TR/ df l t l/http://www.w3.org/TR/rdf‐sparql‐protocol/http://www.w3.org/2004/Talks/17Dec‐

l/i /sparql/intro/ex1.rqhttp://www.oreillynet.com/pub/wlg/7823


THANK YOU…

For your attendance and patience

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ANY QUESTIONS?ANY QUESTIONS?

68

DUAONTOLOGYDUAONTOLOGY

Taxonomy

DuaDua

Qurani Duas Masnoon DuasQurani Duas Masnoon Duas

DuasTo Seek K l d DuasToSeekParadise


Knowledge DuasToSeekParadise ….

RDF Model of Duas

containsDua isRelatedTo

DuaSurahProphet

isRelatedTo

isContainedInhasRelatedDua

hasTheme

Theme


SAMPLE SPARQLQUERIESSAMPLE SPARQLQUERIES

Search Duawith a Particular Theme

PREFIX dua: htt // ti b / t l i /<http://www.semanticweb.org/ontologies/2

008/9/DuaOntology.owl#>

SELECT ?D ?themeWHERE { ?D dua:hasTheme ?theme.}


SAMPLE SPARQL QUERIESSAMPLE SPARQL QUERIES

é éTested with Protégé 3.3.1

PizzaOntology

Querying for Classes


SELECT ?subject ?objectWHERE { ?subject rdfs:subClassOf ?object }


PREFIX p: <http://www.co‐d / t l i / i / / / 8/ iode.org/ontologies/pizza/2005/10/18/pizza.o

wl#>SELECT ? bj t ? bj tSELECT ?subject ?objectWHERE { ?subject rdfs:subClassOf ?object }



wl#>SELECT ? bj t ? bj tSELECT ?subject ?objectWHERE { ?subject rdfs:subClassOf p:Pizza}



wl#>SELECT ? bj t ? bj tSELECT ?subject ?objectWHERE { ?subject rdfs:subClassOf Pi T ip:PizzaTopping.

}


PREFIX p: <http://www.co‐ode org/ontologies/pizza/2005/10/18/pizza oode.org/ontologies/pizza/2005/10/18/pizza.owl#>SELECT ?subject ?objectSELECT ?subject ?objectWHERE { ?subject rdfs:subClassOf p:DomainConcept.p p?subject owl:disjointWith ?object.

}


Dua Ontology

Querying on Instance Data


List all Duas with Corresponding themes



SELECT ?D ?themeWHERE { ?D dua:hasTheme ?theme.}


Example: List of Duas, their Themes which are contained in Surah Taha



SELECT ?D ?themeWHERE { ?D dua:hasTheme ?theme.?D dua:hasSourceSurah dua:Taha. }


List of All Dua’s which have some Theme and have some source Surah



SELECT ?D ?theme ?surahWHERE { ?D dua:hasTheme ?theme.

?D dua:hasSourceSurah ?surah.}


PREFIX dua: <http://www.semanticweb.org/ontologies/2008/9/DuaOntology.owl#>

SELECT ?D ?theme ?surah ?no

WHERE { ?D dua:hasTheme ?themeWHERE { ?D dua:hasTheme ?theme.?D dua:hasSourceSurah ?surah .

?surah dua:hasSurahNo ?no?surah dua:hasSurahNo ?no.

}}ORDER BY ?no



SELECT ?D ?theme ?surah ?no ?ayah

WHERE { ?D dua:hasTheme ?themeWHERE { ?D dua:hasTheme ?theme.?D dua:hasSourceSurah ?surah ;

dua:hasSourceAyah ?ayah.?surah dua:hasSurahNo ?no?surah dua:hasSurahNo ?no.

}}ORDER BY ?no


Notice the change in results with the use of OPTIONALof OPTIONAL


SELECT ?D ?theme ?surah ?no ?ayah

WHERE{ ?D dua:hasTheme ?theme.?D dua:hasSourceSurah ?surah.

?surah dua:hasSurahNo ?no.

OPTIONAL{ ?D dua:hasSourceAyah ?ayah.

}}ORDER BY ?no


Use of Regular Expression to retrieve duas that contain the word Rabbithat contain the word RabbiPREFIX dua: <http://www.semanticweb.org/ontologies/2008/9/DuaOntology.

lowl#>

SELECT ?D ?surah ?no ?text

WHERE{ ?D dua:hasSourceSurah ?surah?D dua:hasSourceSurah ?surah.?D dua:hasTextAyah ?text.

FILTER regex(?text, "Rabbi") .



}

Use of Regular Expression to retrieve duas that contain the word Rabbanathat contain the word Rabbana


SELECT ?D ?surah ?no ?text

WHERE{ WHERE{ ?D dua:hasSourceSurah ?surah.

?D dua:hasTextAyah ?text.FILTER regex(?text "Rabbana") FILTER regex(?text, Rabbana ) .


}


AN interesting Query!. …Think about what it does!what it does!


SELECT ?Dua ?DuaOther ?surah2

WHERE{ WHERE{ ?Dua dua:hasSourceSurah dua:Taha.?Dua dua:isRelatedTo ?p.?DuaOther dua:isRelatedTo ?p?DuaOther dua:isRelatedTo ?p.?DuaOther dua:hasSourceSurah ?surah2.

}}


Find other Duas related to the same prophet in a given Surahprophet in a given Surah

� “Find other duas related with the prophet of a given surah ”given surah.


sparql tutorial ii & iii

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