Instance Flow - modelint/shlaer-mellor-metamodel GitHub Wiki

An Instance Flow communicates zero or more instance references. An instance reference is simply a tuple whose header corresponds to the primary identifier of a Class. The body of this relation will then supply zero or more tuples where each tuple defines an instance of that Class.

The choice of the primary Identifier is an arbitrary convention since no identifier would do the job. There is nothing special about being 'primary' other than a numbering convention.

Identifiers

1. ID + Activity + Domain

Attributes

No non-referential attributes