Object-Role Modeling Terminology
To help learn the terminology of Object-Role Modeling when having come from an Entity-Relationship Diagram or Property-Graph Schema background, the following table of terms and their corresponding terminology has been compiled.
| Object-Role Modeling | Entity-Relationship Diagram | Property Graph Schema |
| Object Type | - Entity | - Node Type |
| Fact Type | - Entity; - Foreign Key Relationship; and - Not Applicable (where a Fact Type defined a Column) |
- Node Type; - Edge Type; - Not Applicable (where a Fact Type defined a Column); - Link (rarely); |
| Value Type | - Not Applicable, however every Column has correspondence with a -Value Type in the corresponding Object-Role Model. | Not Applicable, however every Column has correspondence with a Value Type in the corresponding Object-Role Model. |
| Entity Type | - Entity | Node Type |
| Internal Uniqueness Constraint | - Primary Key; and - Not applicable where an IUC is merely over the Role joining an Object Type and where the Role's Fact Type defines an Attribute or Colum in the Entity-Relationship Diagram and against an Entity; or - May define a Unique Index. |
- Primary Key; and - Not applicable where an IUC is merely over the Role joining an Object Type and where the Role's Fact Type defines an Attribute or Colum in the Entity-Relationship Diagram and against an Entity; or - May define a Unique Index; |
| External Uniqueness Constraint | - Primary Key; or - May define a Unique Index. |
- Primary Key; or - May define a Unique Index. |
| Unary Fact Type | - Attribute (Boolean); | - Attribute (Boolean); |
| Association | - Foreign Key Relationship; and - Many-to-Many Join Table; |
- Edge Type |
| Objectified Fact Type | - Entity | - Node Type |