SPARQL construct to file list
Transformer, allows the user to create multiple RDF files including multiple RDF named graphs using a set of SPARQL CONSTRUCT queries.
- Use deduplication
- Individual SPARQL query results may contain duplicate triples or quads. This is a result of the way the SPARQL queries are evaluated. For smaller files this causes no issues as the duplicates are correctly resolved when the resulting file is further processed. For larger files, it is possible to turn on deduplication, which processes the results when they are serialized. This causes a slight performance penalty.
Characteristics
- ID
- t-sparqlconstructtofilelist
- Type
- transformer
- Inputs
- RDF single graph - Configuration
- RDF single graph - Data
- RDF single graph - Tasks
- Outputs
- Files
- Look in pipeline
The SPARQL construct to file list component queries the Data input using a set of SPARQL CONSTRUCT queries, saving the results as files in the output. The queries and resulting files and named graphs are specified in the Tasks input. Multiple tasks can write to the same file, creating for instance a quad file with multiple named graphs.
Runtime configuration
Below you can see sample runtime configuration for the component. Note that RDF blank nodes are not allowed in runtime configurations.
Task specification
Below you can see sample task specification for the component. This task generates a single TriG file with two named graphs in it, containing metadata records of two DCAT datasets.