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How to use Q Objects Method In Django

Using Union Method

Create a project to apply combine multiple QuerySets in Django

In this example, we use Q objects to create OR conditions for authors from the USA and the UK. We also filter books published after the year 2000. Then, we combine the QuerySets using the chain function.

Python3




from .models import Author, Book
from django.db.models import F
 
authors = Author.objects.annotate(book_count=F('book__count'))
books = Book.objects.annotate(author_name=F('author__name'))
 
combined_queryset = list(chain(authors, books))
 






                        









																																						

																							

											
											

												
How to combine multiple QuerySets in Django?

																								

																										
QuerySets allow you to filter, order, and manipulate data from your database using a high-level Pythonic syntax. However, there are situations where you may need to combine multiple QuerySets into a single QuerySet to work with the data more efficiently. This article will explore various methods to achieve this in Django.

																																						

																							

										


										
										

											
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