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
