Pagination (PageNumber, Cursor, Limit/Offset) in Django - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import the Django paginator class.

Django

from django.core.paginator import [1]

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

APaginator

BLimitOffsetPagination

CCursorPagination

DPage

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Page' instead of 'Paginator' which is not the main class.

Confusing cursor or limit-offset pagination classes with Paginator.

The Paginator class is used for page number pagination in Django.

2fill in blank

medium

Complete the code to create a paginator with 10 items per page.

Django

paginator = Paginator(queryset, [1])

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

A5

B20

C25

D10

Attempts:

3 left

💡 Hint

Common Mistakes

Using 5 or 20 which are valid but not the intended answer here.

Passing the queryset instead of the number.

The second argument to Paginator is the number of items per page. Here, 10 is a common page size.

3fill in blank

hard

Fix the error in retrieving the page object by filling the blank with the correct method call.

Django

page_obj = paginator.[1](page_number)

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

Aget_page_number

Bpage_number

Cget_page

Dpaginate

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'page_number' which is a variable, not a method.

Using 'paginate' which is not a method of Paginator.

The get_page method safely returns the page object for the given page number.

4fill in blank

hard

Fill both blanks to create a cursor pagination class with a page size of 15.

Django

class MyCursorPagination([1]):
    page_size = [2]

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

ACursorPagination

BLimitOffsetPagination

C15

D10

Attempts:

3 left

💡 Hint

Common Mistakes

Using LimitOffsetPagination instead of CursorPagination.

Setting page_size to 10 instead of 15.

Cursor pagination uses the CursorPagination class and the page_size attribute sets how many items per page.

5fill in blank

hard

Fill all three blanks to create a limit-offset pagination class with default limit 20 and max limit 50.

Django

class MyLimitOffsetPagination([1]):
    default_limit = [2]
    max_limit = [3]

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

ALimitOffsetPagination

B20

C50

DCursorPagination

Attempts:

3 left

💡 Hint

Common Mistakes

Using CursorPagination instead of LimitOffsetPagination.

Mixing up default_limit and max_limit values.

Limit-offset pagination uses the LimitOffsetPagination class. The default_limit and max_limit control page size limits.

Practice

1. Which Django REST Framework pagination style uses a page number to fetch specific pages of data?

easy

A. PageNumberPagination

B. CursorPagination

C. LimitOffsetPagination

D. OffsetPagination

Solution

1. Step 1: Understand pagination styles

   PageNumberPagination uses page numbers like 1, 2, 3 to get data pages.

2. Step 2: Match style to description

   CursorPagination uses a cursor token, LimitOffsetPagination uses limit and offset numbers, so they don't use page numbers.

3. Final Answer:

   PageNumberPagination -> Option A

4. Quick Check:

   Page number style = PageNumberPagination [OK]

Hint: PageNumberPagination uses simple page numbers like 1, 2, 3 [OK]

Common Mistakes:

• Confusing CursorPagination with page numbers
• Thinking LimitOffsetPagination uses page numbers
• Assuming OffsetPagination is a valid DRF style

2. Which of the following is the correct way to set LimitOffsetPagination in Django REST Framework settings?

easy

A. "DEFAULT_PAGINATION_CLASS": "rest_framework.pagination.OffsetPagination"

B. "DEFAULT_PAGINATION_CLASS": "rest_framework.pagination.PageNumberPagination"

C. "DEFAULT_PAGINATION_CLASS": "rest_framework.pagination.LimitOffsetPagination"

D. "DEFAULT_PAGINATION_CLASS": "rest_framework.pagination.CursorPagination"

Solution

1. Step 1: Identify correct class path

   LimitOffsetPagination is located at rest_framework.pagination.LimitOffsetPagination.

2. Step 2: Verify syntax for settings

   The setting key is DEFAULT_PAGINATION_CLASS and the value is the full class path as a string.

3. Final Answer:

   "DEFAULT_PAGINATION_CLASS": "rest_framework.pagination.LimitOffsetPagination" -> Option C

4. Quick Check:

   Correct class path and setting key = "DEFAULT_PAGINATION_CLASS": "rest_framework.pagination.LimitOffsetPagination" [OK]

Hint: Use full class path string for pagination in settings [OK]

Common Mistakes:

• Using OffsetPagination which does not exist
• Missing quotes around class path string
• Mixing pagination class names

3. Given this code snippet using CursorPagination, what will be the value of the next cursor if the current cursor is 'abc123' and page size is 2?

class MyCursorPagination(CursorPagination):
    page_size = 2

paginator = MyCursorPagination()
next_cursor = paginator.get_next_link()

medium

A. A tuple with offset and limit values

B. An integer representing the next page number

C. None, because get_next_link() returns nothing

D. A URL containing a cursor parameter with a new encoded cursor

Solution

1. Step 1: Understand CursorPagination behavior

   CursorPagination returns URLs with encoded cursor tokens for next pages, not page numbers or tuples.

2. Step 2: Analyze get_next_link() output

   get_next_link() returns a URL string containing the next cursor parameter for pagination.

3. Final Answer:

   A URL containing a cursor parameter with a new encoded cursor -> Option D

4. Quick Check:

   CursorPagination next link = URL with cursor [OK]

Hint: CursorPagination returns URLs with cursor tokens, not numbers [OK]

Common Mistakes:

• Expecting page numbers from CursorPagination
• Thinking get_next_link() returns None
• Confusing limit/offset with cursor

4. You have this Django REST Framework view using LimitOffsetPagination but it raises an error:

class MyLimitOffsetPagination(LimitOffsetPagination):
    default_limit = '10'

class MyView(ListAPIView):
    pagination_class = MyLimitOffsetPagination
    queryset = MyModel.objects.all()
    serializer_class = MySerializer

What is the likely cause of the error?

medium

A. pagination_class should be a string path, not a class

B. default_limit should be an integer, not a string

C. ListAPIView does not support pagination

D. queryset must be a list, not a QuerySet

Solution

1. Step 1: Check default_limit type

   default_limit must be an integer, but it is set as a string '10', causing a type error.

2. Step 2: Verify other parts

   pagination_class can be a class, ListAPIView supports pagination, queryset can be a QuerySet.

3. Final Answer:

   default_limit should be an integer, not a string -> Option B

4. Quick Check:

   default_limit type error = default_limit should be an integer, not a string [OK]

Hint: default_limit must be int, not quoted string [OK]

Common Mistakes:

• Setting default_limit as string instead of int
• Thinking pagination_class must be string path
• Assuming ListAPIView disables pagination

5. You want to implement pagination for a large dataset where new items are frequently added. Which pagination style is best to avoid duplicate or missing items when users navigate pages?

hard

A. CursorPagination

B. PageNumberPagination

C. LimitOffsetPagination

D. No pagination

Solution

1. Step 1: Understand pagination challenges with dynamic data

   PageNumber and LimitOffset can cause duplicates or missing items if data changes between requests.

2. Step 2: Identify pagination style that handles dynamic data well

   CursorPagination uses a stable cursor based on item order, preventing duplicates or skips when data changes.

3. Final Answer:

   CursorPagination -> Option A

4. Quick Check:

   Dynamic data needs CursorPagination [OK]

Hint: Use CursorPagination for changing data to avoid duplicates [OK]

Common Mistakes:

• Choosing PageNumberPagination for dynamic data
• Thinking LimitOffsetPagination handles data changes well
• Ignoring pagination for large datasets