Asset Oriented Modeling (AOM)

- Step by Step (2) -

Assets and Properties

When we said: "AOM models both nouns and verbs as assets," we did not mean all nouns and verbs:

• Some nouns will be modeled as properties of assets.
• Some verbs, especially verbs that indicate an aggregation (like "has") or a classification (like "is a") are modeled as arcs (see Step 3).

How do we decide which noun will be modeled by a property and which noun will be modeled by an asset?

• In the informal description properties are usually indicated by the verb "has" or other verbs that indicate an aggregation:  
  "An Order has an  Order Number", or "An Institution has a Name".

• Anything which plays a certain role in the context of the business case is definitely an asset.

In many cases the distinction between a property and an asset can be made using a simple rule: 

A property can belong to an asset, but an asset cannot belong to a property.

However, the distinction between property and asset is not always such easy, and may depend on the context. Take for example:

A person has a address.

While in most cases address can be conveniently modeled as a property of person, a utility company, for example, would need to model address as an asset - investments are directly related to addresses, not to persons. If in doubt, whether to model a noun as asset or property, opt for the asset.

With these principles we arrive at the following assets (red) and properties (blue):

A Customer orders Products or Services.

A Customer is a Person or an Institution.

A Person has a Name consisting of FirstName, an optional MiddleName, and a LastName.

A Person has a birthDate.

An Institution has a Name.

A Customer has a CustomerID.

A Department receives these Orders.

A Department has a DepartmentID.

A Department may forward Orders to another Department.

An Order has at least one Position, an OrderDate and an OrderNumber.

Each Position consists of an Amount and a Product or a Service.

A Product has a ProductNo, a Name, and a Description.

A Service has a ProductNo, a Name, a Description, and may have a Duration.

Note:

In the case of Person, Name is a complex property, consisting of sub-properties FirstName, MiddleName, and LastName.

Finally, we decide which properties or property combinations shall be used as primary keys for assets.

Contact: info@aoModeling.org