Initialize an rdf
Object
rdf(storage = c("memory", "BDB", "sqlite", "postgres", "mysql", "virtuoso"), host = NULL, port = NULL, user = NULL, password = NULL, database = NULL, charset = NULL, dir = NULL, dsn = "Local Virtuoso", name = "rdflib", new_db = FALSE, fallback = TRUE)
storage | Storage backend to use; see details |
---|---|
host | host address for mysql, postgres, or virtuoso storage |
port | port for mysql (mysql storage defaults to mysql standard port, 3306) or postgres (postgres storage defaults to postgres standard port, 4321) |
user | user name for postgres, mysql, or virtuoso |
password | password for postgres, mysql, or virtuoso |
database | name of the database to be created/used |
charset | charset for virtuoso database, if desired |
dir | directory of where to write sqlite or berkeley database. |
dsn | Virtuoso dsn, either "Local Virtuoso" or "Remote Virtuoso" |
name | name for the storage object created. Default is usually fine. |
new_db | logical, default FALSE. Create new database or connect to existing? |
fallback | logical, default TRUE. If requested storage system cannot initialize,
should |
an rdf object
an rdf Object is a list of class 'rdf', consisting of
three pointers to external C objects managed by the redland library.
These are the world
object: basically a top-level pointer for
all RDF models, and a model
object: a collection of RDF statements,
and a storage
object, indicating how these statements are stored.
rdflib
defaults to an in-memory hash-based storage structure.
which should be best for most use cases. For very large triplestores,
disk-based storage will be necessary. Enabling external storage devices
will require additional libraries and custom compiling. See the storage
vignette for details.
x <- rdf()