What is the primary role of a primary key in a table?

• To store the most frequently accessed data

• To uniquely identify each record in the table

• To maintain referential integrity

• To create relationships between tables

Which of the following is an example of a one-to-many relationship?

• A student enrolled in multiple courses

• An employee working in a single department

• A product supplied by multiple suppliers

• A customer placing multiple orders

What is a foreign key?

• A key that provides a unique identifier for a table

• A key that links two tables together

• A key that allows many-to-many relationships

• A key that can only be used in one table

In a many-to-many relationship, what is typically used to link two tables?

• Foreign key

• Junction table

• Composite key

• Primary key

Which of the following is a requirement for referential integrity?

Foreign key values must match the primary key in the related table

• Foreign key values must match the primary key in the related table

• Foreign key values must be null

• Primary key values can be duplicated

• Foreign key values must always be unique

What is the main function of a junction table?

• To store additional information about a foreign key

• To establish a one-to-one relationship between tables

• To resolve many-to-many relationships between tables

• To provide alternative foreign keys for a table

If a foreign key in a child table does not have a matching primary key in the parent table, what database issue arises?

• Data inconsistency

• Referential integrity violation

• Data redundancy

• Data normalization

What is a composite key?

• A key composed of multiple foreign keys

• A key made up of two or more columns to uniquely identify records

• A key that enforces referential integrity

• A key used only in junction tables

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

• One record in a table is related to many records in another table

• Many records in one table are related to many records in another table

• One record in a table is related to one record in another table

• A single record in a table can have multiple foreign keys