Help:Property uniqueness

Property uniqueness and hereby its literal (i.e. label) representation is a requirement in Semantic MediaWiki to ensure that ID assignments are distinct and non arbitrary, yet under certain circumstances this requirement can be violated. For example, a user-defined property has turned into a pre-defined property (such as when an extension uses the entity space) with both entity descriptions to remain active.

To avoid contradictory assumptions, Semantic MediaWiki 3.0.0Released on 11 October 2018 and compatible with MW 1.27.0 - 1.31.x.1 and later will show a message on the property page where this requirement no longer holds true. It is expected that a data curator resolves the situation by either:

• Redirecting the entity to an intended target
• Removing the invalid property using the administrative "entity lookup and disposal" function which may require to run the maintenance script "rebuildData.php"Allows to rebuild all the semantic data for a selected data backend/store

If the configuration parameter $smwgFieldTypeFeaturesSets relational database specific field type features is enabled, the detection will also mark misspellings such as "KeyWords" and "Keywords" on behalf of existing property declarations.

See also

• Help page on semantic gardening
• Help page on property similarity
• Help page on property pages
• Help page on object ID lookup and object ID disposal
• Help page on special property "Has uniqueness constraint"Allows to restrict value annotation to be unique (Property value uniqueness constraint)