Description

Qualifiers can be thought of as annotations on statements, which add additional information. For example, many statements giving the population of a geographical region have a qualifier telling when that number was true. References are also annotations on statements; their structure is a bit different but very similar to that of qualifiers. No value claims and some value claims are also a bit different, but closely related.

None of our existing Wikidata-inspired types are quite right for representing these kinds of content. To enable importing them, we need to determine what new types to create for this purpose.

Here are some Wikidata documentation pages for statements and qualifiers. References and no/some value claims can also be found in these documents.

• https://www.mediawiki.org/wiki/Wikibase/DataModel#Statements
• https://doc.wikimedia.org/Wikibase/master/php/docs_topics_json.html#json_statements
• https://doc.wikimedia.org/Wikibase/master/php/docs_topics_json.html#json_qualifiers

Desired behavior/Acceptance criteria (returned value, expected error, performance expectations, etc.)

• We should understand how to represent all qualifiers, references, and no/some value claims in use in Wikidata.

Completion checklist

• Before closing this task, review one by one the checklist available here: https://www.mediawiki.org/wiki/Abstract_Wikipedia_team/Definition_of_Done#Back-end_Task/Bug_completion_checklist