Abstract

This document describes the background and methodology for the design of the Schema.org profile of DCAT-AP (DCAT-AP-SDO), as well as the defined mappings.

Introduction

This document describes the background and methodology for the design of the Schema.org profile of DCAT-AP (DCAT-AP-SDO), as well as the defined mappings.

The motivation for investigating the possiblity of aligning DCAT-AP metadata with Schema.org is twofold:

  1. To identify how to create a DCAT-AP-compliant representation of Schema.org metadata, in order to enable their sharing across DCAT-AP-enabled data catalogues.
  2. To identify how to create a Schema.org-compliant representation of DCAT-AP metadata, in order to enhance their discoverability on the Web.

The following sections first illustrate the background () and methodology () for the design of DCAT-AP-SDO, followed by a summary of the mapping issues ().

The defined mappings are introduced in , and grouped as follows:

A formal definition of the proposed mappings, encoded in the form of SPARQL queries, is included in appendix ().

Background

The DCAT Application Profile for Data Portals in Europe (DCAT-AP)

DCAT-AP [[DCAT-AP]] is a metadata profile developed in the framework of the EU Programme Interoperability Solutions for European Public Administrations (ISA), and based on and compliant with the W3C Data Catalog vocabulary (DCAT) [[VOCAB-DCAT]] - currently, one of the most widely used Semantic Web vocabularies for describing datasets and data catalogues.

The purpose of DCAT-AP is to define a common interchange metadata format for data portals of the EU and of EU Member States. In order to achieve this, DCAT-AP defines a set of classes and properties, grouped into mandatory, recommended and optional. Such classes and properties correspond to information on datasets and data catalogues that are shared by many European data portals, aiding interoperability. Although DCAT-AP is designed to be independent from its actual implementation, RDF [[RDF-CONCEPTS]] and Linked Data [[LD-BOOK]] are the reference technologies.

Schema.org

Schema.org [[SCHEMA-ORG]] is an initiative promoted by Google, Microsoft, Yahoo and Yandex, aiming to develop and maintain metadata vocabularies for the description of Web resources, to be re-used by search engines to enhance online content indexing and discovery.

Since its launch in 2011, Schema.org has incrementally grown to cover a variety of domains, also through the re-use of existing popular vocabularies - as Dublin Core [[DCTERMS]], the Friend Of A Friend (FOAF) vocabulary [[FOAF]], vCard [[vCARD-RDF]], as well as DCAT [[VOCAB-DCAT]]. According to an estimation reported in [[GUHA-2015]], at the end of 2015 the adoption of Schema.org concerned around 12,000,000 Web sites.

Typically, Schema.org is used to embed metadata in Web pages, using mechanisms as Microdata [[MICRODATA]], RDFa [[HTML-RDFa]] and JSON-LD [[JSON-LD]]. The data model is based on and compliant with RDF.

Aligning DCAT-AP with Schema.org

The motivation for investigating the possiblity of aligning DCAT-AP metadata with Schema.org is twofold:

  1. To identify how to create a DCAT-AP-compliant representation of Schema.org metadata, in order to enable their sharing across DCAT-AP-enabled data catalogues.
  2. To identify how to create a Schema.org-compliant representation of DCAT-AP metadata, in order to enhance their discoverability on the Web.

In both cases, this analysis is not meant to provide a complete representation of all DCAT-AP metadata elements and those included in its thematic extensions (e.g., geospatial and statistical), but only of those supported by Schema.org.

Methodology

The reference DCAT-AP and Schema.org specifications used in this exercise are the following ones:

For the mappings, existing work has been taken into account concerning the mapping of Schema.org to other metadata standards. In particular:

DCAT-AP-SDO re-uses these specifications, and extends them to provide an as much as possible complete mapping of the metadata elements in [[DCAT-AP]], [[GeoDCAT-AP]], and [[StatDCAT-AP]].

Summary of alignment issues

A general issue is determined by the fact that Schema.org and DCAT-AP address different use cases. More precisely, the main purpose of Schema.org is to enhance discovery and indexing of online resources via search engines. As such, it is addressing more general objectives compared with DCAT-AP, that is instead meant to model in detail information on datasets and data catalogues.

One of the main consequences is that some information that is relevant in DCAT-AP it is not modelled in Schema.org with specific terms. This results in a relevant amount of (a) "missing" and (b) "many-to-one" mappings - i.e., different metadata elements of DCAT-AP are mapped to the same element in Schema.org.

This is not necessarily a problem, since the objective of mapping DCAT-AP and Schema.org is to enhance discoverability of DCAT-AP metadata on the Web, which does not require a complete, 1-to-1 representation of DCAT-AP metadata. Actually, the result of this exercise can also include the identification of the subset of DCAT-AP metadata elements that is worth representing in a Schema.org-based description. On the other hand, this situation also implies that a reverse mapping (i.e., from Schema.org to DCAT-AP) may be problematic or not possible.

The following sections describe the DCAT-AP metadata elements posing mapping issues.

Categories and category schemes

This concerns classes skos:ConceptScheme and skos:Concept.

Only few of the categories and categories schemes used in DCAT-AP are supported in Schema.org. The re-use of "external" controlled vocabularies is allowed in Schema.org, but how this can be modelled is unclear.

Based on the documentation found online [[WEBSCHEMAS-EE]], the approach seems to be based on the use of schema:Enumeration for skos:ConceptScheme, but it is unclear how to state that a given skos:Concept is in a given skos:ConceptScheme.

Another option could be to use schema:ItemList for skos:ConceptScheme's, and schema:ListItem for skos:Concept's, and to link the two with schema:itemListElement.

Resource "types"

This concerns properties denoting the "type" of a resource, by using a skos:Concept. In DCAT-AP, this is typically done by using property dct:type.

Schema.org has a generic property, namely schema:additionalType - defined as a sub-property of rdf:type, that is meant to be used to associate multiple types with the same resource. It is to be investigated whether it can be used for this purpose.

Provenance

DCAT-AP uses property dct:provenance to specify "provenance statements" about datasets (typically, their lineage).

Schema.org does not have specific terms for this purpose, so a possible option is to use more generic ones, like schema:description.

Conformance

This concerns properties denoting the conformance of a resource with a standard. In DCAT-AP, this is typically done by using property dct:conformsTo, which is used in different contexts (namely, to express conformance with a metadata standard, with a data schema, with a reference system, with given quality criteria).

Schema.org does not have properties for this purpose, and it seems there are no suitable candidates that can be used.

Checksum

DCAT-AP allows the specification of the checksum of a dataset distribution by using specific classes and properties from the Software Package Data Exchange (SDPX) vocabulary [[SPDX]].

Schema.org does not have terms for this purpose, and it seems there are no suitable candidates that can be used.

Licences, standards & al.

Resources as licences and standards are modelled by specific classes and properties in DCAT-AP.

In Schema.org, there is a general "type", namely schema:CreativeWork, further refined with a number of "sub-types" (e.g., schema:Dataset is one of these sub-types). However, none of them is specifically modelling resources as, e.g., licences and standards.

Geometries

This concerns property locn:geometry.

Schema.org uses a specific representation for geometries, whereas locn:geometry supports any type of geometry encoding / representation.

The mapping of locn:geometry to Schema.org may therefore require further processing to convert the original geometry encoding / representation to the target one.

Mapping summary

The following sections summarise the alignments defined in DCAT-AP-SDO.

The alignments cover the metadata elements defined in the following specifications:

For each of the mapped elements and the reference controlled vocabularies, the relevant specification is referred to in the tables included in the following sections.

For Schema.org, the reference specification is Schema.org 3.9 () [[SCHEMA-ORG-20190801]].

The alignments are grouped as follows:

In the mapping tables included in the following sections, column "Obl." ("Obligation"), denotes whether the class / property is mandatory ("M"), recommended ("R"), or optional ("O").

Used namespaces

Prefix Namespace URI Schema & documentation
adms http://www.w3.org/ns/adms# [[VOCAB-ADMS]]
cnt http://www.w3.org/2011/content# [[Content-in-RDF]]
dc http://purl.org/dc/elements/1.1/ [[DC11]]
dcat http://www.w3.org/ns/dcat# [[VOCAB-DCAT]]
dct http://purl.org/dc/terms/ [[DCTERMS]]
dctype http://purl.org/dc/dcmitype/ [[DCTERMS]]
dqv http://www.w3.org/ns/dqv# [[VOCAB-DQV]]
foaf http://xmlns.com/foaf/0.1/ [[FOAF]]
gsp http://www.opengis.net/ont/geosparql# [[GeoSPARQL]]
locn http://www.w3.org/ns/locn# [[LOCN]]
oa http://www.w3.org/ns/oa# [[ANNOTATION-VOCAB]]
owl http://www.w3.org/2002/07/owl# [[OWL-REF]]
prov http://www.w3.org/ns/prov# [[PROV-O]]
qb http://purl.org/linked-data/cube# [[VOCAB-DATA-CUBE]]
rdf http://www.w3.org/1999/02/22-rdf-syntax-ns# [[RDF-CONCEPTS]]
rdfs http://www.w3.org/2000/01/rdf-schema# [[RDF-SCHEMA]]
schema http://schema.org/ [[SCHEMA-ORG]]
skos http://www.w3.org/2004/02/skos/core# [[SKOS-REFERENCE]]
spdx http://spdx.org/rdf/terms# [[SPDX]]
stat http://data.europa.eu/m8g/ [[StatDCAT-AP]]
vcard http://www.w3.org/2006/vcard/ns# [[vCARD-RDF]]
xsd http://www.w3.org/2001/XMLSchema# [[XMLSCHEMA11-2]]

Reference code lists for metadata elements

Specification Metadata elements Code list URI Code lists Status
[[DCAT-AP]] Catalogue record change type http://purl.org/adms/changetype ADMS Change Type controlled vocabulary [[ADMS-SKOS]] stable
[[GeoDCAT-AP]] Degree of conformity http://inspire.ec.europa.eu/metadata-codelist/DegreeOfConformity [[INSPIRE-DoC]] stable
[[DCAT-AP]] Distribution status http://purl.org/adms/status ADMS Status controlled vocabulary [[ADMS-SKOS]] stable
[[StatDCAT-AP]] Distribution type http://publications.europa.eu/resource/authority/distribution-type [[MDR-DT]] stable
[[DCAT-AP]] Format http://publications.europa.eu/resource/authority/file-type [[MDR-FT]] stable
[[GeoDCAT-AP]] INSPIRE spatial data themes http://inspire.ec.europa.eu/theme [[INSPIRE-THEMES]] stable
[[DCAT-AP]] Geographical names http://publications.europa.eu/resource/authority/continent [[MDR-CONT]] stable
http://publications.europa.eu/resource/authority/country [[MDR-COUNTRIES]] stable
http://publications.europa.eu/resource/authority/place [[MDR-PLACES]] stable
http://sws.geonames.org/ [[GEONAMES]] stable
[[DCAT-AP]] Language http://publications.europa.eu/resource/authority/language [[MDR-LANG]] stable
[[DCAT-AP]] Licence type http://purl.org/adms/licencetype ADMS Licence Type controlled vocabulary [[ADMS-SKOS]] stable
[[DCAT-AP]] Maintenance frequency (Maintenance information) http://publications.europa.eu/resource/authority/frequency [[MDR-FREQ]] stable
[[GeoDCAT-AP]] http://inspire.ec.europa.eu/metadata-codelist/MaintenanceFrequencyCode Register operated by the INSPIRE Registry for maintenance frequency codes defined in ISO 19115 [[ISO-19115]]. The register is not yet available, and the code list URI is tentative. unstable
[[DCAT-AP]] MDR Data themes http://publications.europa.eu/resource/authority/theme [[MDR-THEMES]] stable
[[DCAT-AP]] Media type http://www.iana.org/assignments/media-types [[IANA-MEDIA-TYPES]] stable
[[DCAT-AP]] Publisher http://publications.europa.eu/resource/authority/corporate-body [[MDR-CB]] stable
[[DCAT-AP]] Publisher type http://purl.org/adms/publishertype ADMS Publisher Type controlled vocabulary [[ADMS-SKOS]] stable
[[GeoDCAT-AP]] Reference system type http://inspire.ec.europa.eu/glossary/SpatialReferenceSystem [[INSPIRE-GLOSSARY]]. testing
http://inspire.ec.europa.eu/glossary/TemporalReferenceSystem
[[GeoDCAT-AP]] Resource type http://inspire.ec.europa.eu/metadata-codelist/ResourceType [[INSPIRE-RT]] stable
[[GeoDCAT-AP]] Responsible party role http://inspire.ec.europa.eu/metadata-codelist/ResponsiblePartyRole [[INSPIRE-RPR]] stable
[[GeoDCAT-AP]] Service type http://inspire.ec.europa.eu/metadata-codelist/SpatialDataServiceType [[INSPIRE-SDST]] stable
[[GeoDCAT-AP]] Spatial data service categories http://inspire.ec.europa.eu/metadata-codelist/SpatialDataServiceCategory [[INSPIRE-SDSC]] stable
[[GeoDCAT-AP]] Spatial representation type http://inspire.ec.europa.eu/metadata-codelist/SpatialRepresentationTypeCode Register operated by the INSPIRE Registry for spatial representation type codes defined in ISO 19115 [[ISO-19115]]. The register is not yet available, and the code list URI is tentative. unstable
[[GeoDCAT-AP]] Topic category http://inspire.ec.europa.eu/metadata-codelist/TopicCategory [[INSPIRE-TC]] stable

Classes

DCAT-AP Schema.org Comments
Specification Obl. Label QName
[[DCAT-AP]] M Agent foaf:Agent schema:Organization | schema:Person
[[DCAT-AP]] M Catalogue dcat:Catalog schema:DataCatalog
[[DCAT-AP]] M Dataset dcat:Dataset schema:Dataset
[[DCAT-AP]] R Category skos:Concept schema:Thing TBD
[[DCAT-AP]] R Category Scheme skos:ConceptScheme schema:Enumeration TBD
[[DCAT-AP]] R Distribution dcat:Distribution schema:DataDownload
[[DCAT-AP]] R Licence Document dct:LicenseDocument schema:CreativeWork | schema:URL TDB
[[DCAT-AP]] O Catalogue Record dcat:CatalogRecord schema:ListItem
[[DCAT-AP]] O Checksum spdx:Checksum schema:Thing TBD
[[DCAT-AP]] O Document foaf:Document schema:CreativeWork | schema:URL TBD
[[DCAT-AP]] O Identifier adms:Identifier schema:PropertyValue schema:PropertyValue is the mechanism currently recommended in Schema.org to specify identifiers modelled as structured objects.
[[DCAT-AP]] O Kind vcard:Kind schema:ContactPoint
[[DCAT-AP]] O Location dct:Location schema:Place
[[DCAT-AP]] O Media Type or Extent dct:MediaTypeOrExtent schema:Text | schema:URL TBD
[[DCAT-AP]] O Period of Time dct:PeriodOfTime schema:DateTime
[[DCAT-AP]] O Provenance Statement dct:ProvenanceStatement schema:CreativeWork | schema:URL TBD
[[GeoDCAT-AP]] O Reference System dct:Standard schema:CreativeWork | schema:URL TBD
[[DCAT-AP]] O Rights Statement dct:RightsStatement schema:CreativeWork | schema:URL TBD
[[GeoDCAT-AP]] O Service dctype:Service schema:Service
[[DCAT-AP]] O Standard dct:Standard schema:CreativeWork | schema:URL TBD

Properties for mandatory classes

Agent

These properties should be used with schema:Organization or schema:Person (formal definition in ).

DCAT-AP Schema.org Comments
Specification Obl. Label QName
[[DCAT-AP]] M name foaf:name schema:name
[[DCAT-AP]] R type dct:type schema:?? TBD
[[GeoDCAT-AP]] O email foaf:mbox schema:email
[[GeoDCAT-AP]] O homepage foaf:workplaceHomepage schema:url

Catalogue

These properties should be used with schema:DataCatalog (formal definition in ).

DCAT-AP Schema.org Comments
Specification Obl. Label QName
[[DCAT-AP]] M dataset dcat:dataset schema:dataset
[[DCAT-AP]] M description dct:description schema:description
[[DCAT-AP]] M publisher dct:publisher schema:publisher
[[DCAT-AP]] M title dct:title schema:name
[[DCAT-AP]] R homepage foaf:homepage schema:url
[[DCAT-AP]] R language dct:language schema:inLanguage
[[DCAT-AP]] R licence dct:license schema:license
[[DCAT-AP]] R release date dct:issued schema:datePublished
[[DCAT-AP]] R themes dcat:themeTaxonomy schema:?? TBD
[[DCAT-AP]] R update / modification date dct:modified schema:dateModified
[[GeoDCAT-AP]] O creation date dct:created schema:dateCreated
[[DCAT-AP]] O has part dct:hasPart schema:hasPart
[[DCAT-AP]] O is part of dct:isPartOf schema:isPartOf
[[DCAT-AP]] O record dcat:record schema:itemListElement
[[DCAT-AP]] O rights dct:rights schema:?? TBD
[[DCAT-AP]] O spatial / geographic coverage dct:spatial schema:spatialCoverage

Dataset

These properties should be used with schema:Dataset (formal definition in ).

DCAT-AP Schema.org Comments
Specification Obl. Label QName
[[DCAT-AP]] M description dct:description schema:description
[[DCAT-AP]] M title dct:title schema:name
[[DCAT-AP]] R contact point dcat:contactPoint schema:contactPoint
[[DCAT-AP]] R dataset distribution dcat:distribution schema:distribution
[[DCAT-AP]] R keyword dcat:keyword schema:keywords
[[DCAT-AP]] R publisher dct:publisher schema:publisher
[[DCAT-AP]] R theme / category dcat:theme schema:about
[[DCAT-AP]] O access rights dct:accessRights schema:?? TBD
[[StatDCAT-AP]] O attribute stat:attribute schema:?? TBD
[[GeoDCAT-AP]] O author dct:creator schema:creator
[[GeoDCAT-AP]] O conformance result / conformity (data quality) dct:conformsTo schema:?? TBD
[[DCAT-AP]] O conforms to dct:conformsTo schema:?? TBD
[[GeoDCAT-AP]] O creation date dct:created schema:dateCreated
[[StatDCAT-AP]] O dimension stat:dimension schema:?? TBD
[[DCAT-AP]] O documentation foaf:page schema:mainEntityOfPage
[[DCAT-AP]] O frequency dct:accrualPeriodicity schema:?? TBD
[[DCAT-AP]] O has version dct:hasVersion schema:?? TBD
[[DCAT-AP]] O identifier dct:identifier schema:identifier
[[DCAT-AP]] O is version of dct:isVersionOf schema:?? TBD
[[DCAT-AP]] O landing page dcat:landingPage schema:url
[[DCAT-AP]] O language dct:language schema:inLanguage
[[StatDCAT-AP]] O number of data series stat:numberOfDataSeries schema:?? TBD
[[DCAT-AP]] O other identifier adms:identifier schema:identifier Schema.org does not currently provide a way to denote "other" identifiers.
[[GeoDCAT-AP]] O owner dct:rightsHolder schema:copyrightHolder
[[DCAT-AP]] O provenance dct:provenance schema:?? TBD
[[StatDCAT-AP]] O quality annotation dqv:hasQualityAnnotation schema:review
[[GeoDCAT-AP]] O reference system dct:conformsTo schema:?? TBD
[[DCAT-AP]] O related resource dct:relation schema:mentions
[[DCAT-AP]] O release date dct:issued schema:datePublished
[[DCAT-AP]] O sample amds:sample schema:?? TBD
[[DCAT-AP]] O source dct:source schema:isBasedOnUrl
[[DCAT-AP]] O spatial / geographic coverage dct:spatial schema:spatialCoverage
[[GeoDCAT-AP]] O spatial resolution rdfs:comment schema:?? TBD
[[DCAT-AP]] O temporal coverage dct:temporal schema:temporalCoverage
[[GeoDCAT-AP]] O topic category dct:subject schema:about
[[DCAT-AP]] O type dct:type schema:?? TBD
[[StatDCAT-AP]] O unit of measurement stat:unitOfMeasurement schema:?? TBD
[[DCAT-AP]] O update / modification date dct:modified schema:dateModified
[[DCAT-AP]] O version owl:versionInfo schema:version
[[DCAT-AP]] O version notes adms:versionNotes schema:?? TBD

Properties for optional classes

Catalogue record

These properties should be used with schema:ListItem (formal definition in ).

DCAT-AP Schema.org Comments
Specification Obl. Label QName
[[DCAT-AP]] M primary topic foaf:primaryTopic schema:item
[[DCAT-AP]] M update / modification date dct:modified schema:dateModified
[[DCAT-AP]] R application profile dct:conformsTo schema:?? TBD
[[DCAT-AP]] R change type amds:status schema:?? TBD
[[DCAT-AP]] R listing date dct:issued schema:datePublished
[[GeoDCAT-AP]] O character encoding cnt:characterEncoding schema:?? TBD
[[GeoDCAT-AP]] O contact point dcat:contactPoint schema:contactPoint
[[DCAT-AP]] O description dct:description schema:description
[[GeoDCAT-AP]] O identifier dct:identifier schema:identifier
[[DCAT-AP]] O language dct:language schema:inLanguage
[[DCAT-AP]] O source metadata dct:source schema:isBasedOnUrl
[[DCAT-AP]] O title dct:title schema:name

Checksum

TBD (formal definition in ).

DCAT-AP Schema.org Comments
Specification Obl. Label QName
[[DCAT-AP]] M algorithm spdx:algorithm schema:?? TBD
[[DCAT-AP]] M checksum value spdx:checksumValue schema:?? TBD

Document

TBD (formal definition in ).

DCAT-AP Schema.org Comments
Specification Obl. Label QName
[[GeoDCAT-AP]] O description dct:description schema:description
[[GeoDCAT-AP]] O title dct:title schema:name

Identifier

These properties should be used with schema:PropertyValue (formal definition in ).

DCAT-AP Schema.org Comments
Specification Obl. Label QName
[[DCAT-AP]] M notation skos:notation schema:value The actual identifier string
[[DCAT-AP]] O notation skos:notation/@rdf:datatype schema:propertyID The type of identifier

Kind

These properties should be used with schema:ContactPoint (formal definition in ).

DCAT-AP Schema.org Comments
Specification Obl. Label QName
[[DCAT-AP-IG]] R name vcard:fn schema:name
[[DCAT-AP-IG]] R email vcard:hasEmail schema:email
[[GeoDCAT-AP]] O
[[GeoDCAT-AP]] O organisation name vcard:organization-name schema:name
[[GeoDCAT-AP]] O homepage vcard:hasURL schema:url
[[DCAT-AP-IG]]
[[DCAT-AP-IG]] O telephone vcard:hasTelephone schema:telephone

Location

These properties should be used with schema:Place (formal definition in ).

DCAT-AP Schema.org Comments
Specification Obl. Label QName
[[GeoDCAT-AP]] O geographical identifier dct:identifier schema:identifier
[[GeoDCAT-AP]] O geographical identifier / name authority skos:inScheme schema:?? TBD. The "authority" denotes the reference register for the geographical name / identifier (typically, a gazetteer).
[[GeoDCAT-AP]] O geographical name skos:prefLabel schema:name
[[GeoDCAT-AP]] O geometry locn:geometry schema:geo

Schema.org expects as value an instance of schema:GeoCoordinates (for points) or schema:GeoShape (for more complex geometries).

LOCN allows any type of geometry, and any type of geometry encoding / representation—including those supported by Schema.org.

As a consequence, the locn:geometry mapping might require further processing to encode the geometry according the encodings supported in Schema.org.

Media type or extent

TBD (formal definition in ).

DCAT-AP Schema.org Comments
Specification Obl. Label QName
[[GeoDCAT-AP]] O label rdfs:label schema:name

Period of time

These properties should be used with schema:DateTime (formal definition in ).

DCAT-AP Schema.org Comments
Specification Obl. Label QName
[[DCAT-AP]] O start date / time schema:startDate schema:startDate
[[DCAT-AP]] O end date / time schema:endDate schema:endDate

Provenance statement

TBD (formal definition in ).

DCAT-AP Schema.org Comments
Specification Obl. Label QName
[[GeoDCAT-AP]] O name / description rdfs:label schema:?? TBD

Reference system

TBD (formal definition in ).

DCAT-AP Schema.org Comments
Specification Obl. Label QName
[[GeoDCAT-AP]] O reference system authority skos:inScheme schema:?? TBD. The "authority" denotes the reference register for the reference system.
[[GeoDCAT-AP]] O reference system identifier dct:identifier schema:identifier
[[GeoDCAT-AP]] O reference system name skos:prefLabel schema:name
[[GeoDCAT-AP]] O reference system type (e.g., spatial, temporal) dct:type schema:?? TBD
[[GeoDCAT-AP]] O reference system version owl:versionInfo schema:version

Rights statement

TBD (formal definition in ).

DCAT-AP Schema.org Comments
Specification Obl. Label QName
[[GeoDCAT-AP]] O name / description rdfs:label schema:?? TBD

Service

These properties should be used with schema:Service (formal definition in ).

DCAT-AP Schema.org Comments
Specification Obl. Label QName
[[GeoDCAT-AP]] O access rights dct:accessRights schema:?? TBD
[[GeoDCAT-AP]] O author dct:creator schema:creator
[[GeoDCAT-AP]] O conformance result / conformity (data quality) dct:conformsTo schema:?? TBD
[[GeoDCAT-AP]] O conforms to dct:conformsTo schema:?? TBD
[[GeoDCAT-AP]] O contact point dcat:contactPoint schema:contactPoint
[[GeoDCAT-AP]] O coupled resource dct:hasPart schema:hasPart
[[GeoDCAT-AP]] O creation date dct:created schema:dateCreated
[[GeoDCAT-AP]] O description dct:description schema:description
[[GeoDCAT-AP]] O keyword (free text) dc:subject schema:keywords
[[GeoDCAT-AP]] O keyword (from a controlled vocabulary) dct:subject schema:about
[[GeoDCAT-AP]] O language dct:language schema:inLanguage
[[GeoDCAT-AP]] O publisher dct:publisher schema:publisher
[[GeoDCAT-AP]] O release date dct:issued schema:datePublished
[[GeoDCAT-AP]] O resource locator foaf:homepage schema:url TBD
[[GeoDCAT-AP]] O spatial / geographic coverage dct:spatial schema:spatialCoverage
[[GeoDCAT-AP]] O spatial data service category dct:type schema:?? TBD
[[GeoDCAT-AP]] O spatial data service type dct:type schema:?? TBD
[[GeoDCAT-AP]] O temporal coverage dct:temporal schema:temporalCoverage
[[GeoDCAT-AP]] O title dct:title schema:name
[[GeoDCAT-AP]] O type dct:type schema:?? TBD
[[GeoDCAT-AP]] O update / modification date dct:modified schema:dateModified

Standard

TBD (formal definition in ).

DCAT-AP Schema.org Comments
Specification Obl. Label QName
[[GeoDCAT-AP]] O creation date dct:created schema:dateCreated
[[GeoDCAT-AP]] O release date dct:issued schema:datePublished
[[GeoDCAT-AP]] O title dct:title schema:name
[[GeoDCAT-AP]] O update / modification date dct:modified schema:dateModified
[[GeoDCAT-AP]] O version owl:versionInfo schema:version

SPARQL implementation

This section illustrates a tentative implementation of the mappings defined in DCAT-AP-SDO, in the form of SPARQL CONSTRUCT queries.

The mappings have been defined in a modular way, with a separate SPARQL query for each of the DCAT-AP classes, and related properties. A complete representation of a given resource (e.g., a dataset) and related resource (e.g., distribution, licence, publisher) can be obtained by combining the relevant SPARQL queries.

The source SPARQL queries are maintained in the dedicated GitHub repository.

Agent

For the corresponding mapping table, see .


Catalogue

For the corresponding mapping table, see .


Dataset

For the corresponding mapping table, see .


Category

For the corresponding mapping table, see .


Category scheme

For the corresponding mapping table, see .


Distribution

For the corresponding mapping table, see .


Licence document

For the corresponding mapping table, see .


Catalogue record

For the corresponding mapping table, see .


Checksum

For the corresponding mapping table, see .


Document

For the corresponding mapping table, see .


Identifier

For the corresponding mapping table, see .


Kind

For the corresponding mapping table, see .


Location

For the corresponding mapping table, see .


Media type of extent

For the corresponding mapping table, see .


Period of time

For the corresponding mapping table, see .


Provenance statement

For the corresponding mapping table, see .


Reference system

For the corresponding mapping table, see .


Rights statement

For the corresponding mapping table, see .


Service

For the corresponding mapping table, see .


Standard

For the corresponding mapping table, see .