G2GML¶

G2GML is a RDF Graph to Property Graph Mapping Language.

Overview¶

G2GML defines mapping from RDF graphs to property graphs.
Mapping is described with a set of pairs of RDF graph patterns and property graph patterns.
RDF graph patterns are written in WHERE clause syntax of SPARQL, while the property graph patterns are written in MATCH clause syntax of Cypher.

sample.g2g

<prefix>

<property graph patterns>           <-- Cypher MATCH clause syntax
    <semantic graph patterns>       <-- SPARQL WHERE clause syntax

...

Minimal Examples¶

RDF resource > PG node
RDF datatype property > PG node property
RDF object property > PG edge

RDF resource > PG node¶

mini-01.ttl

@prefix : <http://example.org/> .
:person1 a :Person .

mini-01.g2g

PREFIX : <http://example.org/>
(p:Person)                          <-- PG node is defined
    ?p a :Person .

mini-01.pg

"http://example.org/person1"	 :"Person"

RDF datatype property > PG node property¶

mini-02.ttl

@prefix : <http://example.org/> .
:person1 a :Person .
:person1 :age 30 .

mini-02.g2g

PREFIX : <http://example.org/>
(p:Person {age:a})                 <-- PG node property is defined
    ?p a :Person .
    ?p :age ?a .

mini-02.pg

"http://example.org/person1"	 :"Person"	"age":30

RDF object property > PG edge¶

mini-03.ttl

@prefix : <http://example.org/> .
:person1 a :Person .
:person2 a :Person .
:person1 :follows :person2 .

mini-03.g2g

PREFIX : <http://example.org/>
(p:Person)
    ?p a :Person .
(p1:Person)-[:follows]->(p2:Person)       <-- PG edge is defined
    ?p1 :follows ?p2 .

mini-03.pg

"http://example.org/person1"	 :"Person"
"http://example.org/person2"	 :"Person"
"http://example.org/person1"	->	"http://example.org/person2"	:follows

Actual Examples¶

musician.g2g

PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX prop-ja: <http://ja.dbpedia.org/property/>
PREFIX schema: <http://schema.org/>
PREFIX dbpedia-owl: <http://dbpedia.org/ontology/>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>

# Node mappings

(mus:Musician {vis_label:nam, born:dat, hometown:twn, pageLength:len})
    ?mus rdf:type foaf:Person, dbpedia-owl:MusicalArtist .
    ?mus rdfs:label ?nam .
    FILTER(lang(?nam) = "en") .
    OPTIONAL { ?mus prop-ja:born ?dat }
    OPTIONAL { ?mus dbpedia-owl:hometown / rdfs:label ?twn }
    OPTIONAL { ?mus dbpedia-owl:wikiPageLength ?len }

# Edge mappings

(mus1:Musician)-[:same_group {label:nam, hometown:twn, pageLength:len}]-(mus2:Musician)
    ?grp a schema:MusicGroup ;
         dbpedia-owl:bandMember ?mus1 , ?mus2 .
    FILTER(?mus1 != ?mus2)
    OPTIONAL { ?grp rdfs:label ?nam. FILTER(lang(?nam) = "en")}
    OPTIONAL { ?grp dbpedia-owl:hometown / rdfs:label ?twn }
    OPTIONAL { ?grp dbpedia-owl:wikiPageLength ?len }

(mus1:Musician)-[:influenced]-(mus2:Musician)
    ?mus1 dbpedia-owl:influenced ?mus2 .