User-defined relationships between an individual and a class

latest update 30 Jan. 2015


In ISO 15926-2 you will find only one relationship between an individual and a class: Classification. But in real life there are cases where such an "asymmetric" relationship is required, such as "Ford [an individual] manufactures Mustangs [a class]". For those cases the model offers a way out: the ClassOfRelationshipWithRelatedEnd1 or ClassOfRelationshipWithRelatedEnd2

WARNING - Do not use this lightly, because it may turn out to be nonsensical and the exchange of information may fail for that reason.


Of the two attributes of ClassOfRelationshipWithSignature, classOfEnd1 and classOfEnd2, one can be overriden by an attribute that points at an instance of Thing, i.e. anything you want to point at (even when it's nonsense). This is done by introducing either the ClassOfRelationshipWithRelatedEnd1 or ClassOfRelationshipWithRelatedEnd2.

NOTE - End1 is the attribute, in the EXPRESS model, whose name (in English) is lowest in alphabetical order, or when using an instance of ClassOfRelationshipWithSignature, that is lowest in the alphabetical order of the names (in English) of the instances of Role that are used.

John Doe may marry a woman as of his 18th birthday, using a ClassOfRelationshipWithRelatedEnd1

The conversion of the attribute (property) names, if so required, shall be done with a rule.

This is, of course, not an industrial case, so let us look at another, more appropriate, example. The case for that is that we want to express the fact that a temporal part of the XYZ Ltd performs the pump maintenance activities in the plant of ABC Corp.

The XYZ Ltd is the contractor in all pump maintenance activities in the plant of the ABC Corp

From the above diagram the template below is derived: