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To associate a value with individual defined provenance metadata record
Further Information
Provided by: Semantic MediaWiki
Added in version: 2.5
Removed in version: still in use
Table of Contents
Semantic MediaWiki statement containing a factual claim
Example definition of a property using the Reference type
Example value assignment with tooltip

Reference 1 is a datatype that got introduced with SMW 2.5 and is to associate a value with an individual defined provenance metadata record.

This page is mainly concerned with the [[Has type::Reference]] declaration but you may want to read Referenced statement to find some background on the reasoning for this datatype.

Features and limitations

  • An annotation which requires (or expects) a reference is added as concatenated string separated by ;
  • In case a value itself contains ; as part of its declaration then \; is to be used to distinguish it from the separator
  • Annotations of type Reference work in the same way other types do and can be combined with #set or #subobject
  • Type and position of provenance data fields are fixed by the position used in the Has fields declaration
  • By convention the first field of the Has fields declaration is expected to describe the value property (equivalent to just declaring [[Has type:: ... ]] without provenance data)
  • Value with a reference will be shown a marker to indicate additional information being available which when hovered over to display a tooltip with those additional value statements
  • A reference to a value will in most cases (when displayed as in-text or as result of a #ask query) be displayed as tooltip
  • Queries (same as with those of the Record type) can specify the level of granularity with which an entity is expected to match (Has population::?;>2000]] vs. Has population::>30000000]])

For an exhaustive description, please see the #18081 issue.