com.bigdata.rdf.store
Interface BNS

public interface BNS

A vocabulary for bigdata specific extensions.

Version:

$Id: BNS.java 2265 2009-10-26 12:51:06Z thompsonbry $

Author:

Bryan Thompson

Field Summary

static String	NAMESPACE The namespace used for bigdata specific extensions.
static String	NULL_GRAPH Sesame has the notion of a "null" graph.
static String	SEARCH The name of a magic predicate recognized by the BigdataSail when it occurs in statement patterns such as:
static String	SID The name of a per-statement attribute whose value is recognized in RDF/XML as the statement identifier for statement described by the element on which it appears.
static String	STATEMENT_TYPE The name of a per-statement attribute whose indicates whether the statement is an axiom, inference, or explicit in the knowledge base.

Field Detail

NAMESPACE

static final String NAMESPACE

The namespace used for bigdata specific extensions.

See Also:

Constant Field Values

SID

static final String SID

The name of a per-statement attribute whose value is recognized in RDF/XML as the statement identifier for statement described by the element on which it appears. The bigdata:sid attribute is allowed on elements describing RDF statements and serves as a per-statement identifier. The value of the bigdata:sid attribute must conform to the syntactic constraints of a blank node. By re-using the value of the bigdata:sid attribute within other statements in the same RDF/XML document, the client can express statements about the statements.

This RDF/XML extension allows us to inline provenance (statements about statements) with RDF/XML to clients in a manner which has minor impact on unaware clients (they will perceive additional statements whose predicate is bigdata:sid). In addition, clients aware of this extension can submit RDF/XML with inline provenance.

For example:

 <rdf:Description rdf:about="http://www.foo.org/A">
     <label bigdata:sid="_S67" xmlns="http://www.w3.org/2000/01/rdf-schema#">abc</label>
 </rdf:Description>
 

See Also:

Constant Field Values

STATEMENT_TYPE

static final String STATEMENT_TYPE

The name of a per-statement attribute whose indicates whether the statement is an axiom, inference, or explicit in the knowledge base. This attribute is strictly informative for clients and is ignored when loading data into a knowledge base.

The value will be one of

Axiom

The statement is an axiom that has not been explicitly asserted.

Inferred

The statement is an inference that has not been explicitly asserted.

Explicit

The statement has been explicitly asserted.

Note: If the knowledge base supports truth maintenance and an explicit statement is deleted from the knowledge base but it remains provable as an inference or an axiom then then knowledge base will continue to report it as either an axiom or an inference as appropriate.

See Also:

Constant Field Values

SEARCH

static final String SEARCH

The name of a magic predicate recognized by the BigdataSail when it occurs in statement patterns such as:

 
 ( s?, bigdata:search, "scale-out RDF triplestore" )
 
 

The value MUST be bound and MUST be a literal. The languageCode attribute is permitted, but a datatype attribute is not allowed. When specified, the languageCode attribute will be used to determine how the literal is tokenized - it does not filter for matches marked with that languageCode attribute.

The subject MUST NOT be bound.

This expression will evaluate to a set of bindings for the subject position corresponding to the indexed literals matching any of the terms obtained when the literal was tokenized.

Note: The context position should be unbound when using statement identifiers.

See Also:

Constant Field Values

NULL_GRAPH

static final String NULL_GRAPH

Sesame has the notion of a "null" graph. Any time you insert a statement into a quad store and the context position is not specified, it is actually inserted into this "null" graph. If SPARQL DATASET is not specified, then all contexts are queried and you will see statements from the "null" graph as well as from any other context. com.bigdata.rdf.sail.BigdataSailConnection#getStatements(Resource, URI, Value, boolean, Resource...) will return statements from the "null" graph if the context is either unbound or is an array whose sole element is null.

See Also:

com.bigdata.rdf.sail.BigdataSailConnection#addStatement(Resource, URI, Value, Resource...), com.bigdata.rdf.sail.BigdataSailConnection#getStatements(Resource, URI, Value, boolean, Resource...), Constant Field Values