Prefix and Namespace

The query language uses XML QNames as defined in Namespaces in XML [XML-NS] to represent RDF URI references. QNames have a namespace name which is a URI reference and a local name. QNames are written with a prefix that denote the namespace name. The RDF URI reference represented by a QName is determined by appending the local name part of the QName after the namespace name (URI reference) part of the QName.

The query language recognizes a set of predefined prefix and namespaces :

• rdf : RDF namespace (http://www.w3.org/1999/02/22-rdf-syntax-ns$\sharp$)
• rdfs : RDFS namespace (http://www.w3.org/2000/01/rdf-schema$\sharp$)
• owl : OWL namespace (http://www.w3.org/2002/07/owl$\sharp$)
• xsd : XML Schema Datatype namespace (http://www.w3.org/2001/XMLSchema$\sharp$)
• cos : Corese namespace (http://www.inria.fr/acacia/corese$\sharp$)

It is possible to define local prefixes in a query :

kmp as http://www.inria.fr/acacia/2003/kmp#

dc as http://purl.org/dc/elements/1.1/

Application specific prefix can also be statically defined in a Corese application and then used in queries.