Exam 2: Database Requirements and ER Modeling

SUNSHINE AIRLINE COMPANY The ER Diagram for the SUNSHINE AIRLINE COMPANY is based on the following: - For each airplane type,we keep track of a unique airplane type ID (AirplaneTypeID),number of engines (NoOfEngines),and number of seats (NoOfSeats). - For each airport,we keep track of a unique airport ID (AirportID),and the length of the main runway (LengthOfRunway). - Each airplane type is able to land at one airport at least,but may be able to land at many airports.Each airport accommodates landing of at least one airplane type,but may accommodate landing of more airplane types. This ER diagram will be used for the following questions citing SUNSHINE AIRLINE ER Diagram. -In the ER Diagram for the SUNSHINE AIRLINE COMPANY,Symbol2 should be:

ZYX COMPANY Observe the ER diagram for the ZYX COMPANY: This ER diagram will be used for the following questions citing ZYX Company ER Diagram. -Which of the following is true according to the ZYX Company ER diagram?

Exact maximum cardinality is calculated by adding the exact minimum cardinalities.

A multivalued composite attribute can be used to depict which of the following weak entity concepts?

Maximum cardinality can be optional.

A relationship of degree 3 (also known as a ternary relationship)depicts 3 or more entities involved in one relationship.

EAGLERUN TRUCKING DISPATCHER Observe the ER diagram for the Eaglerun Trucking Dispatcher: This ER diagram will be used for the following questions citing Eaglerun Trucking Dispatcher ER Diagram. -According to the Eaglerun Trucking Dispatcher ER diagram,a driver can drive two trucks.

ZYX COMPANY Observe the ER diagram for the ZYX COMPANY: This ER diagram will be used for the following questions citing ZYX Company ER Diagram. -Which of the following is true according to the ZYX Company ER diagram?

Create an ER diagram based on the following requirements: The database will keep track of students and colleges. - For each student,we will keep track of his or her name and unique student ID. - For each college,we will keep track of its unique name and its location. - Each student in the database attends exactly one college. - Each college in the database has multiple students. - For each student,we keep track of the date he or she started attending his or her college.

CENTRAL SCHOOL LIBRARY Observe the ER diagram for the CENTRAL SCHOOL LIBRARY -Which of the following is NOT true according to the Central School Library ER diagram?

EAGLERUN TRUCKING DISPATCHER Observe the ER diagram for the Eaglerun Trucking Dispatcher: This ER diagram will be used for the following questions citing Eaglerun Trucking Dispatcher ER Diagram. -According to the Eaglerun Trucking Dispatcher ER diagram,a driver can own two trucks.

What is a partial key?

Create an ER diagram based on the following requirements: The database will keep track of students and campus organizations. - For each student,we will keep track of his or her unique student ID,and his or her name and gender. - For each organization,we will keep track of its unique organization ID and the location. - Each student in the database belongs to at least one organization and can belong to multiple organizations. - Each organization in the database has at least one student belonging to it and can have multiple students. - For every instance of a student belonging to an organization,we will record the student's function in the organization (e.g. ,president,vice president,treasurer,member,etc. ).

What is a candidate key?

EAGLERUN TRUCKING DISPATCHER Observe the ER diagram for the Eaglerun Trucking Dispatcher: This ER diagram will be used for the following questions citing Eaglerun Trucking Dispatcher ER Diagram. -According to the Eaglerun Trucking Dispatcher ER diagram,we will keep track of the same number of trucks and drivers.

ZYX COMPANY Observe the ER diagram for the ZYX COMPANY: This ER diagram will be used for the following questions citing ZYX Company ER Diagram. -Which of the following is true according to the ZYX Company ER diagram?

EAGLERUN TRUCKING DISPATCHER Observe the ER diagram for the Eaglerun Trucking Dispatcher: This ER diagram will be used for the following questions citing Eaglerun Trucking Dispatcher ER Diagram. -According to the Eaglerun Trucking Dispatcher ER diagram,each truck has a unique TruckID value.

SUNSHINE AIRLINE COMPANY The ER Diagram for the SUNSHINE AIRLINE COMPANY is based on the following: - For each airplane type,we keep track of a unique airplane type ID (AirplaneTypeID),number of engines (NoOfEngines),and number of seats (NoOfSeats). - For each airport,we keep track of a unique airport ID (AirportID),and the length of the main runway (LengthOfRunway). - Each airplane type is able to land at one airport at least,but may be able to land at many airports.Each airport accommodates landing of at least one airplane type,but may accommodate landing of more airplane types. This ER diagram will be used for the following questions citing SUNSHINE AIRLINE ER Diagram. -In the ER Diagram for the SUNSHINE AIRLINE COMPANY,which word should replace xxx?

Each instance of a weak entity must participate in one instance of the identifying relationship.

Attribute B of EntityX is a: