Pagination (PageNumber, Cursor, Limit/Offset) in Django - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ component_behavior

intermediate

What is the output of this Django PageNumberPagination response?

Given a Django REST Framework view using PageNumberPagination with page_size=3, what will the JSON response contain when requesting page 2?

Django

from rest_framework.pagination import PageNumberPagination
from rest_framework.response import Response

class MyPagination(PageNumberPagination):
    page_size = 3

# Assume queryset has 7 items indexed 1 to 7

# Request: GET /items/?page=2

# What will be the 'results' length in the response?

A The 'results' list will contain 3 items (items 4, 5, 6).

B The 'results' list will contain 1 item (item 7 only).

C The 'results' list will contain 4 items (items 4, 5, 6, 7).

D The 'results' list will be empty because page 2 is invalid.

💡 Hint

PageNumberPagination divides items into pages of fixed size. Page 1 has items 1-3, page 2 has items 4-6, and so on.

With 7 items and page size 3, page 1 has items 1-3, page 2 has items 4-6, and page 3 has item 7. So page 2 returns 3 items.

📝 Syntax

intermediate

Which option correctly sets up CursorPagination in Django REST Framework?

Choose the correct way to define a cursor pagination class with a page size of 5 and ordering by 'created' field.

A

class MyCursorPagination(CursorPagination):
    page_size = 5
    ordering = 'created'

B

class MyCursorPagination(CursorPagination):
    page_size = 5
    ordering = created

C

class MyCursorPagination(CursorPagination):
    page_size = 5
    ordering = ('created')

D

class MyCursorPagination(CursorPagination):
    page_size = 5
    ordering = ['created']

💡 Hint

The ordering attribute expects an iterable of strings.

The ordering attribute must be a list or tuple of strings. Option D uses a list with one string 'created'.

🔧 Debug

advanced

Why does this LimitOffsetPagination code raise a TypeError?

Examine the following Django REST Framework pagination class and identify why it raises a TypeError when used.

Django

from rest_framework.pagination import LimitOffsetPagination

class MyLimitOffsetPagination(LimitOffsetPagination):
    default_limit = '10'

# Using this pagination causes TypeError: unsupported operand type(s) for -: 'str' and 'int'

A The class must define a max_limit attribute to avoid errors.

B LimitOffsetPagination requires overriding the paginate_queryset method.

C default_limit is set as a string instead of an integer.

D The TypeError is caused by missing a call to super().__init__() in the class.

💡 Hint

Check the type of default_limit and how it is used internally.

LimitOffsetPagination expects default_limit as an integer. Setting it as a string causes arithmetic operations to fail.

❓ state_output

advanced

What is the value of 'next' in this PageNumberPagination response?

Given a queryset of 12 items and PageNumberPagination with page_size=5, what will the 'next' URL be when requesting page 2?

Django

# Request: GET /api/items/?page=2
# Page size: 5
# Total items: 12

# What is the 'next' URL in the paginated response?

A "/api/items/?page=3"

B "/api/items/?page=4"

C null

D "/api/items/?page=2"

💡 Hint

Calculate total pages and which page comes after page 2.

With 12 items and page size 5, total pages = 3 (5+5+2). Page 2's next page is page 3, so 'next' URL points to page 3.

🧠 Conceptual

expert

Which pagination method is best for infinite scrolling with stable ordering?

You want to implement infinite scrolling in a Django REST Framework API. The data changes frequently, and you want to avoid skipping or repeating items when users scroll. Which pagination method is best?

A LimitOffsetPagination because it allows skipping items by offset.

B CursorPagination because it uses a cursor to track position and handles data changes well.

C PageNumberPagination because it is simple and uses page numbers.

D No pagination; load all items at once for smooth scrolling.

💡 Hint

Consider how data changes affect pagination stability and user experience.

CursorPagination uses a cursor based on item ordering, preventing duplicates or skips even if data changes. It is ideal for infinite scrolling.