This document discusses how to use Semantic MediaWiki (SMW) to publish open linked data. SMW can annotate data with metadata and export it using semantic web standards. The document provides examples of how to link SMW data to external identifiers like Wikidata, use external vocabularies via import declarations, and reconcile SMW data with Wikidata to enable data sharing across platforms. Future developments may improve integration with Wikidata through properties mapping and data pushing capabilities.

1. CC-BY · page 1
Linked (Open) Data with SMW
#SMWCon, November 26, 2020
Bernhard Krabina

2. www.kdz.eu
Semantic MediaWiki
 Collaborative data curation tool
 Metadata tool (Content + Metadata)
 Annotate data in texts
 Knowledge Graph Interface
 Web-based database
 Open-Source, with vibrant community
 Uses Semantic Web Standards
 Internal querying of data
 Importing and exporting of data
 Business logic can be implemented by
customization, without PHP programming

3. www.kdz.eu
The Web is evolving…

4. www.kdz.eu
Defining Linked Data

5. www.kdz.eu
5 Star-Schema of Linked (Open) Data

6. www.kdz.eu
Linked Data vs. Open data
26 November 2020 · Seite 6

7. www.kdz.eu
Open Data and SMW
 Make your SMW readable by everyone
 editing can still be restricted to logged-in users
 Include an open license
 see https://www.mediawiki.org/wiki/Manual:Copyright
 Make it easy for users to access your data:
 SMW puts a link to the RDF-representation (Special:ExportRDF) in the
HTML automatically, see https://www.semantic-
mediawiki.org/wiki/Help:RDF_export
 create an RDF Dump https://www.semantic-
mediawiki.org/wiki/Help:Maintenance_script_dumpRDF.php
 indicate exporting of data on pages or lists (e. g. vCard, iCalendar,
BibTex, KML)
 provide export pages with explanations and several result formats
(CSV, JSON, RDF)

8. www.kdz.eu
Example: FINA Wiki
 https://fina.oeaw.ac.at/wiki

9. www.kdz.eu
Linking to external identifiers
 Define a property
 Assign datatype
„External identifier“
 Links to external ids
 Look for other identifiers
 ORCID https://orcid.org/
 GND
 …..
[[Has type::External identifier]]
[[External formatter uri::http://www.wikidata.org/entity/$1]]

10. www.kdz.eu
Excursion: Service Links
 Only works in Special:Browse
https://github.com/SemanticMediaWiki/SemanticMediaWiki/issues/4020
Property:WikidataID [[provides service::wikidata]]
MediaWiki:Smw_service_wikidata:
Wikidata|http://www.wikidata.org/entity/$1

11. www.kdz.eu
Using External Vocabularies
 Add a page MediaWiki:Smw import foaf
 Instead of local datatype declarations, use
[[Imported from::foaf:familyName]]
on the property page (e. g. Property:Last name)
 To change a datatype, change it on MediaWiki:Smw
import foaf
 https://www.semantic-mediawiki.org/wiki/Help:
Import_vocabulary
 https://github.com/TIBHannover/ontology2smw/tree/issue31_ontologies_wout_aeon
Ad more vocabulary
terms any time…

12. www.kdz.eu
Using Page ID a unique ID
 Define a property
 Assign datatype „Text“
 Set property in template
https://fina.oeaw.ac.at/wiki/?curid=10415
 For „Magic Word“ {{PAGEID}} see
 https://www.mediawiki.org/wiki/Help:
Magic_words#Technical_metadata
 https://www.mediawiki.org/wiki/Manual:
Page_table#page_id
{{#set:FINA ID={{PAGEID}}}}

13. www.kdz.eu
Excursion: PageIDs
 Set another property PageID
 datatype „Page“
 Use „Query forms“ for an ID
lookup
 See Page Forms extension
 https://www.mediawiki.org/wiki/Extension:
Page_Forms/Creating_query_forms

14. www.kdz.eu
Suggest Wikidata property

15. www.kdz.eu
Wikidata Mix‘n‘Match
 https://meta.wikimedia.org/wiki/Mix%27n%27match/Manual
 With „Templatefile“ format, it should be possible
to provide a Mix‘n‘match file:
 https://www.semantic-mediawiki.org/wiki/Help:Templatefile_format
 To be used by the M‘n‘M importer
 https://mix-n-match.toolforge.org/import.php

16. www.kdz.eu
BEACON
 https://www.semantic-
mediawiki.org/wiki/Help:BEACON

17. www.kdz.eu
Reconciliation / OpenRefine
 SMW can provide „result formats“ RDF, JSON,
CSV, etc.
 these an be accessed directly in OpenRefine
 “Reconciliation”
means to look for
data matches with
WikiData
 SMW can re-import
data via DataTransfer
extension

18. www.kdz.eu
The Future (of Knowledge Sharing)
 reuse of „Service links“?
 SMW could use the „Reconciliation API“ of
Wikidata
 https://github.com/OpenRefine/OpenRefine/wiki/Reconciliation-Service-API
 Flexibility of SMW property declaration could be
used to map to Wikidata properties
 assign SMW Property:Country to P17
[[Imported from::ow:equivalentClass::P17]]
 this changes RDF output, does not (yet) trigger feature inside SMW
 pushing data to Wikidata (or other repos): should be doable inside
SMW: on a per-entry-base or batch

19. www.kdz.eu
Contact
19
Bernhard Krabina
 krabina@kdz.or.at
 www.kdz.or.at
 @krabina