ERD

Which type of entity that cannot exist in the database unless another type of entity also exists in the database?

• Weak Entity

• Strong Entity

• Composite Entity

• Primary Key Dependent Entity

An entity who has recursive relationship with itself is called as

• Primary relationship

• Binary relationship

• Ternary relationship

• Unary relationship

A rectangle represents which of the following in Chen’s notation ERD?

• Attributes

• Optional One

• Entity

• Relationship

A lecturer may teach up to four subjects. A subject may be taught by many lecturers.

Based on the scenario above, which of the following is CORRECT Entity diagram for above statement?

• 
• 
• 
• 

Multivalued attributes should ________ be eliminated.

• always

• commonly

• seldom

• never

Customer is uniquely identify by customer ID, customer name, and contact no. A customer may have more than one contact number.

Find the correct ERD that represents the above Business Rules.

• 
• 
• 
• 

In ERD, the relationship is represented in ___________ shape.

• Rectangular

• Square

• Circle

• Diamond

The one guideline to be followed while designing the database is

• A database design may be ambiguous.

• Unrelated data should be at the same table so that updating the data will be easy.

• It should avoid/reduce the redundancy.

• An entity should not have attributes.

________ is an attribute that can uniquely identify all columns in a table.

• Composite attribute

• Primary key

• Multivalued attribute

• Foreign key

Branch have many departments, and each department must belong in one branch. Branch is identify by BranchID, BranchName, Location. Department is identify by DepartmentID, DepartmentName, EmployeeID.

Based on the above business rules, the foreign key should be placed at which entity?

• Branch

• Employee

• Department

• None of the above