Synonyms and Homonyms

Sometimes choosing a single name for an object class is not practical. Different user perspectives may require different vocabularies. For example, a researcher may refer to an Arachnid, while other zoo employees may refer to the same object class as Spider. This is shown on an ORM diagram with a vertical bar between the names.

When an object class appears twice in an ORM with the same name, it is understood to be the same object class. When there is a need for distinct object classes with (almost) the same name, a subscripted number is added to the name to uniquely identify each object class.

Here is a short quiz so you can test your understanding.

Go to the OSA Tutorial ORM

Go to High-Level Relationship Sets Object-Behavior Model

Last updated 27 Sept 1994 by Barry Roberts

(barry@parlant.com)