Why relationships model real-world data in Django - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a Django model with a foreign key relationship.

Django

class Book(models.Model):
    author = models.ForeignKey([1], on_delete=models.CASCADE)
    title = models.CharField(max_length=100)

Drag options to blanks, or click blank then click option'

AAuthor

Bmodels.CharField

CBook

DForeignKey

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong model name in ForeignKey

Forgetting to import the related model

The ForeignKey field links the Book model to the Author model, showing a real-world relationship where a book has an author.

2fill in blank

medium

Complete the code to add a many-to-many relationship between students and courses.

Django

class Student(models.Model):
    courses = models.[1](Course)
    name = models.CharField(max_length=50)

Drag options to blanks, or click blank then click option'

AForeignKey

BManyToManyField

CCharField

DOneToOneField

Attempts:

3 left

💡 Hint

Common Mistakes

Using ForeignKey instead of ManyToManyField

Not specifying the related model

ManyToManyField is used to model a many-to-many relationship, like students enrolled in multiple courses.

3fill in blank

hard

Fix the error in the model relationship by completing the code.

Django

class Profile(models.Model):
    user = models.OneToOneField([1], on_delete=models.CASCADE)
    bio = models.TextField()

Drag options to blanks, or click blank then click option'

AUser

BProfile

Cmodels.TextField

DForeignKey

Attempts:

3 left

💡 Hint

Common Mistakes

Linking to the wrong model

Using ForeignKey instead of OneToOneField

The OneToOneField should link to the User model to represent a one-to-one relationship between a profile and a user.

4fill in blank

hard

Fill both blanks to create a dictionary comprehension that maps each course name to the number of students enrolled, filtering courses with more than 5 students.

Django

course_counts = {course.name: [1] for course in courses if [2] > 5}

Drag options to blanks, or click blank then click option'

Acourse.students.count()

Blen(course.students)

Ccourse.students.count

Dcourse.students

Attempts:

3 left

💡 Hint

Common Mistakes

Using len() on a related manager

Using the attribute without calling count()

Use course.students.count() to get the number of students enrolled in each course and filter courses with more than 5 students.

5fill in blank

hard

Fill all three blanks to create a queryset filtering authors who have written more than 3 books and order them by name.

Django

authors = Author.objects.annotate(book_count=[1]).filter([2]__gt=[3]).order_by('name')

Drag options to blanks, or click blank then click option'

ACount('book')

Bbook_count

C3

Dfilter

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong annotation syntax

Filtering on the wrong field

Not ordering correctly

Use Count('book') to annotate the number of books per author, filter authors with book_count > 3, and order by name.