[det]rdf_load(+FileOrList,
:Options)Load RDF data. Options provides additional processing
options. Defined options are:
- blank_nodes(+ShareMode)
- How to handle equivalent blank nodes. If
share
(default),
equivalent blank nodes are shared in the same resource.
- base_uri(+URI)
- URI that is used for rdf:about="" and other RDF constructs
that are relative to the base uri. Default is the source URL.
- concurrent(+Jobs)
- If FileOrList is a list of files, process the input files
using Jobs threads concurrently. Default is the mininum of
the number of cores and the number of inputs. Higher values can be
useful when loading inputs from (slow) network connections. Using 1
(one) does not use separate worker threads.
- format(+Format)
- Specify the source format explicitly. Normally this is deduced from the
filename extension or the mime-type. The core library understands the
formats xml (RDF/XML) and triples (internal quick load and cache
format). Plugins, such as
library(semweb/turtle)
extend the
set of recognised extensions.
- graph(?Graph)
- Named graph in which to load the data. It is not allowed to load
two sources into the same named graph. If Graph is unbound,
it is unified to the graph into which the data is loaded. The default
graph is a
file://
URL when loading a file or, if the
specification is a URL, its normalized version without the optional #fragment.
- if(Condition)
- When to load the file. One of
true
, changed
(default) or
not_loaded
.
- modified(-Modified)
- Unify Modified with one of
not_modified
, cached(File)
,
last_modified(Stamp)
or unknown
.
- cache(Bool)
- If
false
, do not use or create a cache file.
- register_namespaces(Bool)
- If
true
(default false
), register xmlns
namespace declarations or Turtle @prefix
prefixes using
rdf_register_prefix/3
if there is no conflict.
- silent(+Bool)
- If
true
, the message reporting completion is printed using
level silent
. Otherwise the level is informational
.
See also print_message/2.
- prefixes(-Prefixes)
- Returns the prefixes defined in the source data file as a list of pairs.
- multifile
Boolean+
- Indicate that the addressed graph may be populated with triples from
multiple sources. This disables caching and avoids that an rdf_load/2
call affecting the specified graph cleans the graph.
Other options are forwarded to process_rdf/3.
By default,
rdf_load/2 only loads RDF/XML
from files. It can be extended to load data from other formats and
locations using plugins. The full set of plugins relevant to support
different formats and locations is below:
:- use_module(library(semweb/turtle)). % Turtle and TriG
:- use_module(library(semweb/rdf_ntriples)).
:- use_module(library(semweb/rdf_zlib_plugin)).
:- use_module(library(semweb/rdf_http_plugin)).
:- use_module(library(http/http_ssl_plugin)).
- See also
- rdf_db:rdf_open_hook/3,
library(semweb/rdf_persistency)
and
library(semweb/rdf_cache)