module 6

Open Ended

How do primary and foreign keys contribute to the process of database design?

Multiple Choice

Why is it important to understand relationships when designing a database?

• To improve database performance

• To ensure data integrity and accurate representation

• To reduce the cost of database software

• To make databases look visually appealing

Multiple Choice

Which SQL command is used to create a view of data from a relational database?

• INSERT INTO

• CREATE VIEW

• UPDATE VIEW

• SELECT VIEW

Multiple Choice

Which of the following attributes are included in the Payroll_View but not in the HR_View?

• Salary

• HireDate

• EmpName

• DeptName

Multiple Choice

Which abbreviation is used to identify alternate keys in Database Design Language (DBDL)?

• PK

• AK

• SK

• FK

Multiple Choice

Based on the entity definitions, which attributes are used as foreign keys in the SECTION entity?

• CourseID and InstructorID

• SectionID and Year

• DeptID and OfficePhone

• Term and Capacity

Multiple Choice

Which of the following key types in DBDL notation is used to enforce uniqueness but is not the primary key?

• SK (surrogate key)

• AK (alternate/unique key)

• FK (foreign key)

• CK (check key)

Open Ended

Explain how DBDL notation helps in determining which fields should be indexed in a relational database.

Multiple Choice

Which fields in the book database should NOT be indexed according to the indexing strategy, and why?

• PublishedYear and CopiesAvailable, because they are rarely used for filtering and are constantly updated

• Title and Author, because they are common search terms

• ISBN and Genre, because they are unique and useful for reports

• BookID and Title, because they are primary keys

Open Ended

Describe the difference between DBDL notation and E-R diagrams in representing relationships between tables. Use examples from the images to support your answer.

Multiple Choice

In a crow's foot E-R diagram, what does the dash dash symbol represent on the side of the relationship?

• Zero, one, or many

• One and only one

• Primary key

• Foreign key

Open Ended

Explain how referential integrity is enforced in a one-to-many relationship in Microsoft Access E-R diagrams.

Multiple Choice

Which symbols are used in Microsoft Access E-R diagrams to represent the two sides of a one-to-many relationship?

• 1 and infinity

• 1 and zero

• zero and infinity

• one and many

Multiple Choice

Which shapes are used in the E-R model (ERM) to represent entities and relationships?

• Rectangles for entities, diamonds for relationships

• Circles for entities, squares for relationships

• Diamonds for entities, rectangles for relationships

• Triangles for entities, circles for relationships

Multiple Select

Select all correct statements about many-to-many relationships in relational databases.

• They require a composite entity to link tables

• They can be directly created between two tables

• A junction table is used in physical implementation

• The composite entity serves on the 'many' side of one-to-many relationships

Open Ended

Compare how one-to-many and many-to-many relationships are represented in ERM diagrams, using examples from Departments/Employees and Students/Professors.

Multiple Choice

Which of the following best describes a one-to-one relationship in a relational database?

• A relationship where each record in one table relates to only one record in another table

• A relationship where each record in one table relates to multiple records in another table

• A relationship where multiple records in one table relate to multiple records in another table

• A relationship where tables are temporarily connected for data conversion

Multiple Select

Which of the following statements are true about many-to-many relationships in relational databases?

• They require an intermediary table to resolve the relationship

• They can be directly linked without any intermediary table

• They can result in a Cartesian join if not properly resolved

• They are less common than one-to-one relationships

Open Ended

Explain why a junction table is necessary to resolve a many-to-many relationship in a relational database. Use the students and courses example to support your answer.

Multiple Choice

What is the primary purpose of the ENROLLMENTS table in the students and courses database schema?

• To store student grades

• To link students to the courses they enroll in

• To list available courses

• To record course prerequisites

Open Ended

Describe how foreign keys are used in the ENROLLMENTS table to maintain referential integrity in the students and courses database schema.

Multiple Choice

One-to-many relationships in databases are typically implemented using:

• Primary keys only

• Foreign keys

• Unique constraints

• Indexes

Open Ended

Reflecting on today's lesson about database design relationships, what aspect of entity-relationship diagrams do you find most challenging or interesting, and why?