Training modules/dashboard/slides/12814-adhering-to-constraints-wikidata

Adhering to constraints (!) edit

Unsure about that edit you just made? Some Wikidata properties have guiding features called property constraints to show users how to enter the correct data and ensure that items will be formatted correctly.

Properties express how two things relate to each other. In some cases that relationship may be a number, in other cases it may be another item. Property constraints describe the kind of values that properties can have.

An example of a property constraint is the "allowed units constraint", which requires property values to be a specific unit (as opposed to text). The properties and qualifiers P1082 (Population), P2097 (term length), and P670 (street number) all require a numerical value so they use this constraint.