How is transaction management handled within Django and what role do they play in ensuring data integrity?

In Django, transaction management is handled using the django.db.transaction module. Transactions allow grouping multiple database operations into a single unit that either fully completes or is completely rolled back in case of an error. This ensures data integrity and prevents partial changes.

Main ways to manage transactions in Django:

• The @transaction.atomic decorator — wraps a function or method, ensuring that all operations inside are executed within a single transaction.
• The with transaction.atomic(): context manager — explicitly specifies a block of code that should be executed within a transaction.
• Automatic transaction management through the ATOMIC_REQUESTS setting in the database configuration, where each HTTP request is wrapped in a transaction.

Example of usage:

from django.db import transaction

def create_order():
    with transaction.atomic():
        order = Order.objects.create(...)
        # other operations, such as deducting stock
        inventory_item.decrease_stock()
        # if an exception occurs during the process, all changes will be rolled back

Thus, transactions in Django ensure data reliability and consistency, preventing situations where some operations are completed while others are not.