DCAT PR transition

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Transition to Proposed Recommendation

This page is for editors to organize the documentation and evidence necessary to transition a document to Proposed Recommendation. The page's content will be used for the transition request and to inform the transition meeting for that document.

This is a working page for the Government Linked Data working group. It may be subject to change/revision at any time.

Structure taken from W3C Technical Report Development Process.

DCAT Timetable

DCAT CR transition request - for reference


Data Catalog Vocabulary

Current URI

Current CR version: http://www.w3.org/TR/2013/CR-vocab-dcat-20131105/

Proposed PR version: https://dvcs.w3.org/hg/gld/raw-file/default/dcat/static.html

Diff: https://dvcs.w3.org/hg/gld/raw-file/default/dcat/diff.html

Document Abstract

DCAT is an RDF vocabulary designed to facilitate interoperability between data catalogs published on the Web. This document defines the schema and provides examples for its use.

By using DCAT to describe datasets in data catalogs, publishers increase discoverability and enable applications easily to consume metadata from multiple catalogs. It further enables decentralized publishing of catalogs and facilitates federated dataset search across sites. Aggregated DCAT metadata can serve as a manifest file to facilitate digital preservation.

The namespace for all terms in this ontology is: http://www.w3.org/ns/dcat#

The vocabulary defined in this document is also available in these non-normative formats: RDF/XML and Turtle

Status of the document

See proposed PR: https://dvcs.w3.org/hg/gld/raw-file/default/dcat/static.html

This section describes the status of this document at the time of its publication. Other documents may supersede this document. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at http://www.w3.org/TR/.

DCAT was first developed and published by DERI and has seen widespread adoption at the time of this publication. The original vocabulary was further developed by the eGov Interest Group, before being brought onto the Recommendation Track by Government Linked Data (GLD) Working Group.

This document was published by the Government Linked Data Working Group as a Proposed Recommendation. This document is intended to become a W3C Recommendation. The W3C Membership and other interested parties are invited to review the document and send comments to public-gld-comments@w3.org (subscribe, archives) through 12 January 2014. Advisory Committee Representatives should consult their WBS questionnaires. Note that substantive technical comments were expected during the Last Call review period that ended 26 November 2013.

Please see the Working Group's implementation report.

Publication as a Proposed Recommendation does not imply endorsement by the W3C Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.

This document was produced by a group operating under the 5 February 2004 W3C Patent Policy. W3C maintains a public list of any patent disclosures made in connection with the deliverables of the group; that page also includes instructions for disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains Essential Claim(s) must disclose the information in accordance with section 6 of the W3C Patent Policy.

Changes to the document

Substantive changes

There have been no substantive changes.

Noteworthy changes

The document was updated so that all properties defined under the DCAT namespace have their domain explicitly declared in the document. Before the update, the document did not explicitly state the domain of each property but implied its usage in the vocabulary diagram, the textual term description and in the examples.

Minor changes

  • Extending the examples in the document with the properties dct:spatial, dct:temporal and dcat:contactPoint
  • Property: access URL; definition and usage note texts clarified
  • Property: download URL; usage note added to clarify the text and the relationship to dcat:accessURL
  • Property: contact point; change range from vcard:VCard to vcard:Kind. These two classes are equivalent however vcard:VCard is deprecated
  • Property: language; usage note is expanded to describe the case of multiple language datasets
  • Clarification text regarding versioning is added: "DCAT itself does not define properties specific to APIs description. These are considered out of the scope of this version of the vocabulary. Nevertheless, this can be defined as a profile of the DCAT vocabulary."

Evidence of wide review

During CR, we addressed non-critical outstanding comments from the end of LC and the comments from the sole CR commenter. See DCAT Comments.

The main evidence of wide review is the extensive list at DCAT Implementations. This shows 13 implementation reports including a number of official implementers such as the Spanish ministry of Industry, Energy and Tourism Open Data Catalog, The European Union Open Data Portal and The Quebec government Open Data Portal. The report about aligning the metadata of CKAN with DCAT is worth highlighting as CKAN is a widely used to run open data portals.

Given the nature of the vocabulary no automated conformance checking was possible. In most cases implementers simply provided links to data and WG members reviewed the use of DCAT terms for appropriateness. Implementers in some cases provided description of their usage of the vocabulary terms and sample data.

CR Exit Criteria were: Each term in the DCAT namespace will be properly used by two or more data sources, in conformance with the specification. The Term Usage Table shows the coverage of DCAT terms by these reports. We see broad usage of terms, and all terms, except dcat:byteSize, have at least two independent usage reports.

Although dcat:byteSize has only one conforming usage in the implementation reports to date, it is endorsed by two prospective users in their DCAT profiles:

As such, we do not feel it would be appropriate to remove the term. Usage of this term in the future is expected, as data publication pipelines become more full-featured, and its design is simple and non-controversial.

Evidence that the document satisfies group's requirements

The following is unchanged since CR:

The Working Group's charter calls for development of a standardized vocabulary for data catalogs.

Metadata, suitable for provenance (in coordination the Provenance Interchange Working Group), data catalogs (see the dcat data catalog vocabulary and the Comprehensive Knowledge Archive Network CKAN, and VoiD), data quality, timeliness of data, status, refresh rate, etc..

The document is based on that prior publication of the data catalog vocabulary and provides terms to describe metadata about data sets collected in catalogs and therefore addresses that requirement.

Evidence that issues have been formally addressed

The Issue Tracker shows all issues closed. During CR, two public comments were made and addressed:

ISSUE-70: Commenter suggested we formally state that dcat:downloadURL is a sub property of dcat:accessURL. Even though every downloadURL is, in a sense, a kind of accessURL, after discussion the WG concluded that stating this as a subproperty relation in the ontology was likely to lead to surprising and even unwanted entailments. In particular, we expect some profiles to provide a stronger separation of these terms by restricting accessURL to exclude downloadURL. A usage note was added to the document to clarify this. The WG closed the issue

Action-155: Commenter requested that rdfs:domain declarations be provided for all predicates in DCAT. After discussion, the WG agreed with the commenter and formally added domain declarations (to the ontology and also the definition tables in the spec) that reflected an understanding that was already clear from the prose.

Formal objections

None received.

Dependencies on other groups


Record the group's decision to request advancement


Decision taken during the working group meeting on 5-December-2013

Expected date of publication

17th December 2013