The L7 – Logical Data Model of NAF v4 enables you to model InformationElements, their attributes, and their relationships.
Attributes are local instances of Data Elements. Data Elements form the lowest type of data in System Architect – and comprise the underlying data dictionary. A Data Element may be grouped into a Data Structure (example: the Data Structure “Address” can contain the Data Elements “Street Address”, “City”, “State”, and “Zip Code”).
Both InformationElements, Data Elements, and Data Structures are available in other models of the NAF v4 architecture – for example, you can specify the InformationElements that are transformed by an OperationalActivity in the Op-Pr Operational Processes viewpoint.
Logical ER Diagram versus IDEF1X
The L7 – Logical Data Model is one of two types of logical data models available – the other is the IDEF1X type. The two types of models provide a different notation, and also the Logical ER Model has an extra feature not available in the IDEF1X model – the Logical ER model can be mapped to and from a Physical Data Model. From the Physical model you can generate schema for a database. You can also reverse engineer databases into a Physical Data Model and then map that Physical model to a Logical ER Diagram.
Note If you create an IDEF1X model, you can map it to a Logical ER model and then map that to/from a Physical model.
Mapping the Logical ER Model to an IDEF1X Logical Model or Physical Model
▪You can map an Op-If Operational Information: Logical ER Model to an IDEF1X version of it by selecting Dictionary > Create Data Model > Logical IDEF1X.
▪You can map Op-If Operational Information: Logical ER Model to a Rs-If Resource Information: Physical Model by selecting Dictionary > Create Data Model > Physical Data Model.
Logical ER Model Notation – Default Is “Crow’s Feet”
The default notation for the ER Model is called “Crows-Feet” notation. You may change the notation to UML or other types of notations by selecting Format > Diagram > Notation.
