roqet (1) - Linux Manuals

roqet: Rasqal RDF query utility


roqet - Rasqal RDF query utility


roqet [OPTIONS] <query-URI> [base-URI]
roqet [OPTIONS]-e query-string [base-URI]
roqet [OPTIONS]-p sparql-protocol-service-URI [-e query-string ] [base-URI]


The roqet utility allows querying of RDF content using the Rasqal RDF query library, printing the results in variable bindings, RDF graph or boolean format. The query is read from query-URI and the optional base-URI is used as the base URI of the query if present.


roqet uses the usual GNU command line syntax, with long options starting with two dashes (`-') if supported by the getopt_long function. Otherwise only the short options are available.
-e, --exec QUERY
Execute the query in the argument QUERY instead of reading the query from a URI (when -e / --exec is not given).
-i, --input LANGUAGE
Set the input query LANGUAGE to one of the supported languages which includes 'sparql' (SPARQL Query Language for RDF, default), 'sparql11' and 'laqrs'. The full list of supported languages and subsets is given in the help summary with the -h / --help option.
-p, --protocol SERVICE-URI
Call the SPARQL HTTP protocol SERVICE-URI to execute the query instead of executing it inside the Rasqal query engine locally.
-r, --results FORMAT
Set the query results format.
For variable bindings, the values of FORMAT vary upon what Rasqal supports but include 'simple' for a simple text format (default), 'xml' for the SPARQL Query Results XML format, 'rdfxml' and 'turtle' for RDF syntax formats, and 'json' for a JSON version of the results.
For RDF graph results, the values of FORMAT are 'ntriples' (N-Triples, default), 'rdfxml-abbrev' (RDF/XML Abbreviated), 'rdfxml' (RDF/XML), 'turtle' (Turtle), 'json' (RDF/JSON resource centric), 'json-triples' (RDF/JSON triples) or 'rss-1.0' (RSS 1.0, also an RDF/XML syntax).
The exact list of formats depends on what libraptor2(3) was built with but is given correct in the usage message with -h.


-c, --count
Only count the triples and produce no other output.
-d, --dump-query FORMAT
Print the parsed query out in a given FORMAT one of 'none' (default), 'debug', 'structure' or 'sparql'
-D, --data URI
Add RDF data source URI (not a named graph). If no data sources are given, the query itself must point to the data such as via SPARQL FROM uri statements.
-E, --ignore-errors
Do not print error messages and do not exit with a non-0 status.
-f, --feature NAME(=VALUE)
Set query feature NAME to the VALUE or integer 1 if omitted. The known features can be shown with -f help or --feature help.
-F, --format NAME
Set the data source format name for subsequent data graphs called with -D / --data or -G / --named. The default if this is not specified is for the query engine to guess. The name is a Raptor parser name.
-G, --named URI
Add RDF data source URI (named graph)
-h, --help
Show a summary of the options.
-n, --dryrun
Prepare the query but do not execute it.
-q, --quiet
No extra information messages.
-s, --source URI
Add RDF data source URI (named graph) URI by adding it to the list of query data source URIs. FORMAT to 'simple' (default) or 'xml' (an experimental XML format)
-v, --version
Print the rasqal library version and exit.
-W, --warnings LEVEL
Set the warning LEVEL in the range 0 (do not warn about anything) to 100 (show every warning). The Rasqal default is in the middle (50).


roqet sparql-query-file.rq

Run a SPARQL query contained in the local file sparql-query-file.rq. The data used would be described in FROM statements in the query file.

roqet -q -i sparql

Run a SPARQL query that is in the web at URI without an extra messages (quiet, -q).

roqet -q query-file.rq

Run an query (default languge SPARQL) from a local file query-file.rq but using base URI to resolve any relative URIs.

roqet -q -i sparql -r xml

Run a SPARQL query that is in the web at URI and format the results in the SPARQL Query Results XML format with no extra messages.

roqet -i sparql -e 'SELECT * WHERE { ?s ?p ?o }' -D stuff.rdf

Run a SPARQL query given on the command line against data in the file stuff.rdf. The type of the file will be guessed and likely is of format RDF/XML.


SPARQL Query Language for RDF, Eric Prud'hommeaux and Andy Seaborne (eds), W3C Recommendation, 15 January 2008.

SPARQL Query Results XML Format, Jeen Broekstra and Dave Beckett (eds), W3C Recommendation, 15 January 2008.



Dave Beckett -