Which term is used to describe a recursive relationship involving only one entity?

Which term is used to describe a recursive relationship involving only one entity?

• A. Unary
• B. Binary
• C. Ternary
• D. Composite

Answer: (A)

The term used to describe a recursive relationship involving only one entity is referred to as unary. In data modeling, a unary relationship occurs when an entity is associated with itself. This often arises in scenarios where an entity can be related to another instance of the same entity type, such as in organizational structure or hierarchy representations. For example, consider an employee entity where an employee can be a manager of other employees. Here, the relationship is unary because it pertains only to the employee entity itself, illustrating how instances of the entity relate to one another. In contrast, other relationship types such as binary involve two different entities, ternary involves three different entities, and composite typically refers to a relationship that combines multiple attributes or entities but does not specifically describe the recursion of a single entity. Thus, unary is the correct term for a recursive relationship within just one entity.

The term used to describe a recursive relationship involving only one entity is referred to as unary. In data modeling, a unary relationship occurs when an entity is associated with itself. This often arises in scenarios where an entity can be related to another instance of the same entity type, such as in organizational structure or hierarchy representations.

For example, consider an employee entity where an employee can be a manager of other employees. Here, the relationship is unary because it pertains only to the employee entity itself, illustrating how instances of the entity relate to one another.

In contrast, other relationship types such as binary involve two different entities, ternary involves three different entities, and composite typically refers to a relationship that combines multiple attributes or entities but does not specifically describe the recursion of a single entity. Thus, unary is the correct term for a recursive relationship within just one entity.