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The DQV annotator performs static analysis on incoming datasets. More precisely, the datasets are checked for the presence of a set of properties from the DCAT-AP specification. These do not correlate with the categories mandatory, recommended, and optional from the aforementioned spec. Instead, the list reflects what is considered by Fraunhofer FOKUS to be relevant for achieving a high data quality. This list can be customized by disabling individual properties via config.

Additionally, the Annotator derives the number of stars a dataset achieves based on Tim Berner-Lee's 5 * Open Data. Due to technical limits the four-star rating is currently the highest possible.


This service is a pipe module and can therefore be orchestrated in a pipe. The Annotator accepts RDF datasets (including distributions) as a payload. It either augments an existing metrics graph or creates a new one if none has been provided.

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