Which type of entity has its relationship to another entity determined by an attribute in that other entity called a discriminator?

The type of entity that has its relationship to another entity determined by an attribute in that other entity called a discriminator is known as a Subtype entity.

In a database model, entities are often divided into supertypes and subtypes. A supertype is a generic entity type that has a relationship with one or more subtype entities. The subtype entities inherit attributes from the supertype.

The discriminator, also known as the subtype discriminator, is an attribute of the supertype entity that determines to which subtype entity a supertype occurrence is related. It's essentially a way of distinguishing between different subtypes.

For example, in a database for a school, you might have a supertype entity "Person" with subtypes "Student" and "Teacher". The discriminator could be an attribute such as "Role" in the "Person" entity, which determines whether the person is a student or a teacher.