SPARQL data processing support for Barnard59 Linked Data pipelines using Jena TDB
npm install barnard59-tdbSPARQL 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.
Runs a construct query and returns the result as a RDFJS quad stream.
- query: The SPARQL construct query as a string.
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.
Runs multiple update queries and returns a database dump as a RDFJS quad stream.
- queries: SPARQL update queries as an array of strings.
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All examples/update.ttl literals are updated to examples/outdated.ttl in the first query.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:
``bash``
./node_modules/.bin/barnard59 run --format=text/turtle --pipeline=http://example.org/pipeline#pipeline --verbose examples/update.ttl