[ckan-discuss] Fwd: Comments on DCat

Thu May 31 18:46:25 BST 2012

Email just sent to DCat list.

---------- Forwarded message ----------
From: Rufus Pollock <rufus.pollock at okfn.org>
Date: 31 May 2012 16:59
Subject: Comments on DCat
To: public-gld-comments at w3.org

Hi All,

A few weeks ago I spoke in some detail with Faadi Mali about DCat and
to discuss some suggested modifications. The results of this
discussion are inlined below. I'd be interested to hear people's
thoughts and whether people would be happy to make these
modifications.

Regards,

Rufus

## Dataset concept

* Remove dcat:accessURL and just use Resource (Distribution)

  * Status: agreed and in progress

* Remove dcat:dataDictionary (leave for v2 or v1.1)

  * Better to introduce once practice has established a need and consistent
    usage. One should be parsimonious in generating new properties at this
    early stage.
  * Also currently has Inconsistent usage
  * Status: ticket and discuss

* Remove dcat:dataQuality (ditto)

  * As previous

* Remove dcat:granularity (or specify better)

  * As previous

* Remove dc:references (is it used and how would it be used)

  * Suggest removal since for linking datasets we should have (at some point):
    derives, links_to, sibling, partof
  * Remember that people can always add other attributes they want ...
  * Status: ticket and discuss

* Make clear what is optional versus required (?) e.g.

  * Designate as optional: dcterms:accrualPeriodicity
  * Designate as optional: dcat:theme
  * Resolution: ticket and discuss

Possibly to add (but will not happen for the present):

* version
* partof

## Distribution / Resources concept

* Rename dcat:Distribution to dcat:Resource

  * Distribution has a strong connotation from software of a packaged version
    of the entire dataset whereas, in fact, in most cases it will be a data
    file or API associated to the Dataset for which the term Resource is more
    appropriate.
  * Status: ticket and discuss

* Extend the set of attributes a Resource may have

  * [Optional] Add dc:title to Resource
  * [Optional] dcat:mimetype - see
http://docs.ckan.org/en/latest/domain-model-resource.html

    * http://docs.ckan.org/en/latest/domain-model-resource.html#resource-format-strings
    * could also have mimetypeInner

  * [Optional]: hash (md5 or sha1, must be of form md5:{hash} or sha1:{hash})
  * [Optional]: dc:created and dc:modified

* Size: define it as bytes and add sizeString. That is:

  * dcat:size = number / size in bytes
  * [Add] dcat:sizeString: informal string description size e.g. >1Mb

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