Class RDFLite
In: lib/activerdf_rdflite/rdflite.rb
Parent: ActiveRdfAdapter

RDFLite is a lightweight RDF database on top of sqlite3. It can act as adapter in ActiveRDF. It supports on-disk and in-memory usage, and allows keyword search if ferret is installed.

Methods

add   add_ntriples   clear   delete   dump   flush   load   new   query   size   subproperties   translate  

Constants

SPOC = ['s','p','o','c']   constants for extracting resources/literals from sql results
Resource = /<([^>]*)>/
Literal = /"((?:\\"|[^"])*)"/

Public Class methods

new(params = {})

instantiates RDFLite database available parameters:

  • :location => filepath (defaults to memory)
  • :keyword => true/false (defaults to false)
  • :pidx, :oidx, etc. => true/false (enable/disable these indices)

Public Instance methods

add(s,p,o,c=nil)

adds triple(s,p,o) to datastore s,p must be resources, o can be primitive data or resource

add_ntriples(ntriples, context)

adds ntriples from given context into datastore

clear()

deletes all triples from datastore

delete(s, p, o, c=nil)

deletes triple(s,p,o,c) from datastore symbol parameters match anything: delete(:s,:p,:o) will delete all triples you can specify a context to limit deletion to that context: delete(:s,:p,:o, ‘context’) will delete all triples with that context

dump()

returns all triples in the datastore

flush()

flushes openstanding changes to underlying sqlite3

load(file)

loads triples from file in ntriples format

query(query)

executes ActiveRDF query on datastore

size()

returns the number of triples in the datastore (incl. possible duplicates)

translate(query)

translates ActiveRDF query into internal sqlite query string

[Validate]