barnard59-tdb v0.0.1
barnard59-tdb
SPARQL data processing support for Barnard59 Linked Data pipelines using Jena TDB. All operations provide a readable and writable stream interface. The Writable stream expects RDFJS quads. All incoming quads will be written to a temporary TDB database. A database dump or the result of the query will be written to the readable stream.
Operations
construct
Runs a construct query and returns the result as a RDFJS quad stream.
query
: The SPARQL construct query as a string.
select
Runs a select query and returns each row of the results as single chunk object. The chunk object contains key-value pairs for each variable of the select query.
query
: The SPARQL select query as a string.
update
Runs multiple update queries and returns a database dump as a RDFJS quad stream.
queries
: SPARQL update queries as an array of strings.
Examples
update
The example pipeline in examples/update.ttl
parses the pipeline description in the update.ttl
file and feeds it to the TDB update
operation.
Two queries are used.
All examples/update.ttl
literals are updated to examples/outdated.ttl
in the first query.
And again changed to examples/update.ttl
in the second query.
The TDB data is then serialized to N-Triples and the barnard59
command line tool writes it to stdout
.
The example can be run with the following command:
./node_modules/.bin/barnard59 run --format=text/turtle --pipeline=http://example.org/pipeline#pipeline --verbose examples/update.ttl
4 years ago