Relational Database Model

Each table _______ represents an attribute.

• Dimension

• Value

• Column

• Row

Below are the characteristics of a Relational Table EXCEPT

• A table is perceived as a two-dimensional structure composed of rows and columns.

• Each table row(tuple) represents a single entity occurrence within the entity set.

• Each table column represents an attribute.

• All values in a column may have different data format.

What is the main function of a Primary Key in a table?

• Allows duplicate values

• Stores user passwords

• Uniquely identifies each record

• Links to external files

Which of the following is typically a Foreign Key?

• Subject Code

• Lecturer Name

• Student ID in the Registration table

• Date of Enrollment

A key made from two or more attributes is called a:

• Secondary Key

• Composite Key

• Super Key

• Primary Key

Which of the following can be a Candidate Key in a Lecturer table?

• Date of Birth

• Home Address

• Email

• Gender

What is the main difference between a Super Key and a Candidate Key?

• Super Key cannot be null

• Candidate Key must be the shortest

• Super Key may contain unnecessary attributes

• Candidate Key is used only for one-to-one relationships

A non-unique column often used for searching data is known as a:

• Composite Key

• Candidate Key

• Secondary Key

• Primary Key

The Data Dictionary stores:

• Actual data records

• System logs and reports

• Structure of tables and columns

• User login credentials

The System Catalog in an RDBMS stores information about:

• Table names only

• Types of computers used

• The entire database system metadata

• User-entered comments