Answer Happy

A quick True and False Questions:
⦁ A data model is a plan for a database design
FALSE
⦁ The method of constructing data models used in
the text is the extended entity-relationship (E-R)
model.
⦁ An entity is something that users want to
track.
⦁ Entities of a given type are grouped into
entity classes.
⦁ An entity class is described by the structure
of the entities in that class.
⦁ An entity instance of an entity class is the
representation of a particular entity and is described by the
values of the attributes of the entity.
⦁ An identifier of an entity instance is one or
more attributes that name or identify entity instances.
⦁ A compound identifier is an identifier
consisting of two or more attributes.
⦁ In E-R modeling, an attribute describes the
characteristics of an entity.
⦁ An identifier of an entity instance must
consist of one and only one attribute.