The cardinality constraint owl:minCardinality
is a built-in OWL property that links a restriction class to a data value
belonging to the value space of the XML Schema datatype
A restriction containing an owl:minCardinality constraint describes a class of all individuals that have at least N semantically distinct values (individuals or data values) for the property concerned, where N is the value of the cardinality constraint.
Syntactically, the cardinality constraint is represented as an RDF
property element with the corresponding
The following example describes a class of individuals that have at least two parents:
<owl:onProperty rdf:resource="#hasParent" />
In OWL, like in RDF, it is assumed that any instance of a class may have an arbitrary number (zero or more) of values for a particular property. To make a property required (at least one), to allow only a specific number of values for that property, or to insist that a property must not occur, cardinality constraints can be used. OWL provides three constructs for restricting the cardinality of properties locally within a class context.
NOTE: OWL Lite includes the use of all three types of cardinality constraints, but only when used with the values "0" or "1".
Note that an owl:minCardinality of one or more means that all instances of the class must have a value for the property