Overview and features¶

Ontotext Refine (“Refine”) is a version of the open-source OpenRefine data transformation tool adapted to work with Ontotext GraphDB.

Refine allows fast cleaning, mapping and transformation of any structured data to RDF and loading it to GraphDB.

Refine supports input from:

• Tabular formats (TSV, CSV, *SV)
• Fixed-width text files
• Excel (XLS, XLSX)
• JSON, JSON-LD, XML
• RDF: XML, Turtle/N3
• Google sheets (public or access controlled with OAuth)
• Databases (PostgreSQL, MySQL, MariaDB, SQLite)

You can input data from local files, remote URLs, and clipboard snippets.

Refine enables you to:

• Create projects and upload your data file(s)

• Clean and transform the data using powerful row and column manipulations, faceting, clustering

• Implement complex transformations using:

  • Expressions and GREL (Google Refine Expression Language)
  • GraphDB Functions including SPIN functions
  • Combining datasets between Refine projects by using the cross() function.

• Create a visual RDF mapping of the cleaned data

  • The RDF mapping visual UI is optimized to guide you in defining URLs, choosing the right predicates and types, defining datatypes, etc.
  • Export a respective SPARQL query
  • Export the RDF data

• Expose a virtual SPARQL endpoint that allows you to write complex SPARQL queries

  • Export RDF data using a SPARQL Construct query
  • Load RDF data to a GraphDB repository using Federated SPARQL Update query

You can generate Refine queries from semantic models using Ontotext’s open source rdf2rml toolkit