NAME

     4s-query — Run SPARQL queries on a 4store storage backend

SYNOPSIS

     4s-query kb-name [-f format] [-O optimisation-level] [-I insert-mode] [-r] [-s soft-limit]
              [-b base-URI] [-e] [-P] [query]

              -f      Set the format to output results it, options are "sparql", "text", "json",
                      and "testcase"

              -O, --opt-level
                      Set the optimisation level of the query engine, in the range 0-3.

              -I, --insert
                      Treat CONSTRUCT statements as INSERT statements. This feature is highly
                      experimental and largly untested.

              -r, --restricted
                      Enable query complexity restriction mode

              -s, --soft-limit
                      Override default soft limit on search breadth

              -d, --default-graph
                      Enable SPARQL default graph support

              -b, --base
                      Set base URI for queries

              -e, --explain
                      Return an explanation of the query planner's descisions

              -P      Enable programatic IO mode

INTERACTIVE MODE

     If [query] is ommited then 4s-query goes into interactive mode, suitable for trying queries
     from the command line.

     -P enables programatic interactive mode, suitable for infacing with processes via stdin and
     stdout. Queries are sent as UTF-8 bytes, terminated with "#EOQ" on a line of it's own,
     results are returned, ending with "#EOR".  Interacting with 4store in this way is more
     efficient than using the SPARQL protocol, but non-standard.

SEE ALSO

     4s-import(1), 4s-httpd(1), 4s-backend(1), 4s-delete-model(1)

STANDARDS

     4s-query implements the SPARQL Query Language specification (aka. SPARQL/Query 1.0) and the
     SPARQL Result Format specification (aka. SPARQL/Results 1.0).

     Default graph support is no normally enabled, the --default-graph turns it on, as does
     speicfying FROM <default:> in the query. Data loaded with

     $ 4s-import kb --add -m default: uri/filename

     will be added to the default graph.

EXAMPLES

     $ 4s-query -f sparql demo 'SELECT * WHERE { ?s ?p ?s } LIMIT 10'

     Return 10 random triples from the knowledgebase "demo" in the SPARQL XML result format.

     $ 4s-query -P demo < query.rq

     Run the query in query.rq and output the result to stdout