Database Relationships - Quiz Explanation

The answers you selected are indicated below, along with text that explains the correct answers.
 
1. Which type of relationship uses a junction table?
Please select the best answer.
  A. One-to-many
  B. One-to-one
  C. Many-to-many
  D. Many-to-one
 

The correct answer is C.

The many-to-many relationship is the only relationship type that uses a junction table.


2. How do key fields work with a one-to-one relationship between two tables?
Please select the best answer.
  A. The first table uses the primary key field, and the second table uses a foreign key field.
  B. The first table uses the foreign key field, and the second table uses a primary key field.
  C. Both tables use primary key fields.
  D. Neither table uses primary key fields.
 

The correct answer is C.

Primary key fields in both tables are used to create a one-to-one relationship.

3. How does a many-to-many relationship differ from the other two kinds of relationships?
Please select the best answer.
  A. Primary key fields are used for both sides of the relationship.
  B. Three tables are used instead of two tables.
  C. You can’t use referential integrity.
  D. No primary key fields are used.
 

The correct answer is B.

The fact is that three tables are used to create a many-to-many relationship, whereas the other two types of relationships only use two tables. Choice A is incorrect because the one-to-one relationship is the only relationship that uses only primary key fields. Choice C is wrong because you can use referential integrity with many-to-many relationships. Choice D is incorrect because both primary and foreign key fields are used to make up a many-to-many relationship.