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Networkx. SPARQL, RDF Datasets, FROM, FROM NAMED, and GRAPH - TechnicaLee Speaking. Bob DuCharme suggested that I share this explanation about the role of FROM, FROM NAMED, and GRAPH within a SPARQL query. So here it is… A SPARQL query goes against an RDF dataset. An RDF dataset has two parts: A single default graph -- a set of triples with no name attached to them Zero or more named graphs -- each named graph is a pair of a name and a set of triples The FROM and FROM NAMED clauses are used to specify the RDF dataset. The statement "FROM u" instructs the SPARQL processor to take the graph that it knows as "u", take all the triples from it, and add them to the single default graph. The statement "FROM NAMED x" instructs the SPARQL processor to take the graph that it knows as "x", take all the triples from it, pair it up with the name "x", and add that pair (x, triples from x) as a named graph in the RDF dataset.

All the parts of the query that are outside a GRAPH clause are matched against the single default graph. FROM x FROM NAMED x. Thinkmap Visual Thesaurus - An online thesaurus and dictionary of over 145,000 words that you explore using an interactive map. OWL Example with RDF Graph - Introduction to ontologies and semantic web - tutorial. Let us illustrate the use of OWL vocabulary on an example ontology (inspired by OWL Pizzas): "Pizza has PizzaBase as its base; Pizza is disjoint with PizzaBase; NonVegetarianPizza is exactly Pizza that is not VegetarianPizza; isIngredientOf is a transitive property; isIngredientOf is inverse of hasIngredient". The example expressed in the description logic syntax follows: The same example expressed using OWL Abstract Syntax formulates the same information using LISP-like notation, and in addition uses URI for identification of all classes and properties: Namespace(p = < Ontology( < Class(p:Pizza partial restriction(p:hasBase someValuesFrom(p:PizzaBase))) DisjointClasses(p:Pizza p:PizzaBase) Class(p:NonVegetarianPizza complete intersectionOf(p:Pizza complementOf(p:VegetarianPizza))) ObjectProperty(p:isIngredientOf Transitive inverseOf(p:hasIngredient)) ) Pizza OWL ontology expressed in RDF triples.