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index.md

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 ## Django
 
+- [Automic database transactions](notes/20231213075301.md)
 - [Django form save commit kwarg](notes/20221205115023.md)
 
 ## Dundermethods

notes/20231213075301.md

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+# Automic database transactions
+
+Ensure the integrity of your database transactions with transaction.atomic() which guarantees atomicity: all operations within the block either complete successfully or roll back if an error occurs.
+
+Use it to group related operations (e.g. on multiple related models) into a single unit, ensuring either all succeed or none, maintaining data consistency.
+
+```
+from django.db import transaction
+
+# 1. as context manager
+
+def my_view(request):
+    # Non-atomic operations...
+    with transaction.atomic():
+        # Atomic block starts
+        # Database operations here
+        # Atomic block ends
+
+
+# 2. as decorator
+
+@transaction.atomic
+def my_view(request):
+    # Entire view is an atomic block
+```
+
+Fascinating detail is this multi-use of the atomic object 😍, source:
+
+```
+# https://docs.djangoproject.com/en/4.1/_modules/django/db/transaction/
+
+def atomic(using=None, savepoint=True, durable=False):
+    # Bare decorator: @atomic -- although the first argument is called
+    # `using`, it's actually the function being decorated.
+    if callable(using):
+        return Atomic(DEFAULT_DB_ALIAS, savepoint, durable)(using)
+    # Decorator: @atomic(...) or context manager: with atomic(...): ...
+    else:
+        return Atomic(using, savepoint, durable)
+```
+
+The first if statement checks if the first argument (using) is a callable, which in Python typically is a function. If "using" is a function, it implies that atomic is being used as a decorator.
+
+If atomic is not used as a decorator (meaning the "using" argument is not a callable function), it implies that it's being used as a context manager (so the __enter__ and __exit__ special methods of the Atomic class kick in).
+
+#Django