Information Modeling and Relational Databases, 3rd Edition

ORM Glossary

• This glossary lists key terms and symbols used in Object-Role Modeling (ORM), and briefly explains their meaning. A concise explanation of other technical terms may be found in the chapter summaries. Further details on technical terms may be accessed by using the Index.
• Alethic constraint: Constraint that holds necessarily for all states of the model.
• Arity: Number of roles in a relationship (unary =1, binary = 2, ternary = 3, etc.).
• Asserted fact: Fact that is simply asserted, rather than being derived from others; also called a primitive fact or base fact.
• Asserted subtype: Subtype that is simply asserted (not defined by a subtype definition).
• Assertable role: Role is a fact type that is either asserted or semiderived.
• Association: Relationship ...