An Archetype categorizes classes depending on their behavior in the real world. The Archetype is visually identifiable in the UI due to its coloring (Post-it compatible colors). Only one Archetype may be assigned to one class, so all classes should comfortably and naturally slip into one Archetype, but, as always, there is also a grey area. When in doubt, use Party, Place, Thing.
The tutorials will demonstrate the use of Archetypes.
Archetype | Description |
---|---|
Party, Place, Thing (green) | Anything that is, does, can be touched or has a location.
Something concrete that is central to the business. This includes things and actors that participate in activities and anything that have or can have a location, such as Organisation, Person, Country. Typically a Party, Place, Thing object would and should have a real business key. |
Moment – Interval (red) | Anything that happens, or during which something relevant happens.
Something that has a duration or an event date and is interesting from a business point of view. Projects, all transactions, events, actions, time periods. Typically things that form the basis for fact tables. |
Description (blue) | Anything that neither happens nor can be touched but rather describes something else.
Typically code/name combinations with occasional additional descriptive data. Without exception (almost, at least), a Description object has a business key, which usually is the Code property, or equivalent. |
Role (yellow) | Something that does not have a real world identity of its own, but rather represents something else. This includes straight roles (for example Customer is a role for a Person) as well as descriptions of relationships over time or otherwise.
Some role objects have a business key and some don’t. Pure role objects like Customer may have business keys (Customer number), but role objects that act like many-to-many connectors (Project membership) usually don’t. |
Examples
A person exists. During a project, relevant things happen. There are roles a person may have in a project, and a person has a gender. A person may be an employee, and working in a project at any time.