Property chains and paths

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Query conditions to select
Printout statements to display

The property chains and paths feature allows selecting pages with help of subqueries and property chain conditions. Property chains for conditions, e.g. [[Located in.Capital of::Foo]] was provided for some time and now got extended to supporting the syntax on print requests to retrieve values of a chain member that represent a page node. It was extended with Semantic MediaWiki 2.5.0.1

Using the property chain in the query condition and using it on the result printout are two different distinct processes where matching a query condition is about resolving and finding entities (either as row or edge) that adheres certain codified rules while the result printout chain matching on the other hand is about creating a property path along the entity that was returned as part of a query condition or rule match.

Notes

  • The amount of chain members is currently not limited to a certain depth.
  • Properties identified as being part of a property chain are marked with two little superscripted dots "" which shows all its members when being hovered over.

Examples

Regular use cases
{{#ask:
 [[Category:Country]]
 |?Located in
 |?-Located in
 |?-Located in.Capital of
 |?-Located in.Has population
 |?-Located in.Has population.Retrieved on
 |?-Located in.Has population.Retrieved on=WithCustomTitle
}}

See the live example on <sandbox.semantic-mediawiki.org>

Advanced use cases
{{#ask:
 [[Category:Country]]
 [[Category:P0434]]
 |?Located in.-Located in.-Located in.Capital of.Has subobject.Has population.Number
 |link=none
}}
NoteNote: A query like this example is not recommended since various properties are chained (including inverted) to return the expected printout.

See also

supplemental