Exam 2: Data Models

In Chen notation,entities and relationships have to be oriented horizontally; not vertically.

A(n)'s main function is to help one understand the complexities of the real­world environment.

An implementation-ready data model should contain a description of the data structure that will store the end-user data.

A(n)is a brief,precise,and unambiguous description of a policy,procedure,or principle within a specific organization.

A(n) represents a particular type of object in the real world.

The data model uses the concept of inheritance.

In the model,each parent can have many children,but each child has only one parent.

Even when a good database blueprint is available,an applications programmer's view of the data should match that of the manager and the end user.

What are the sources of business rules,and what is the database designer's role with regard to business rules?

In ,a three­pronged symbol represents the "many" side of the relationship.

A(n)enables a database administrator to describe schema components.

In the model,the user perceives the database as a collection of records in 1:M relationships,where each record can have more than one parent.

In an SQL-based relational database,each table is dependent on every other table.

M:N relationships are not appropriate in a relational model.

Today,most relational database products can be classified as object/relational.