Mastering Django ORM Update Queries — From Basics to Pro Level

Updating data properly is just as important as selecting data.

In this guide, you will learn how to update records correctly in Django ORM — from basic .save() usage to pro techniques like atomic updates, bulk updates, F expressions, and best practices!

📚 1. Basic Update Using .save()

Fetch and modify a single object

user = NewUser.objects.get(pk=1)
user.email = 'newemail@example.com'
user.save()

⚡ 2. Updating Specific Fields with .save(update_fields=[...])

user = NewUser.objects.get(pk=1)
user.email = 'newemail@example.com'
user.save(update_fields=['email'])

🎯 3. Updating Multiple Records at Once Using .update()

NewUser.objects.filter(user_type=2).update(is_active=False)

🧠 4. .save() vs .update() — Key Differences

Aspect.save().update()
Works onSingle objectQuerySet (multiple)
Triggers signals?✅ Yes❌ No
Auto-updates auto_now fields?✅ Yes❌ No
Custom logic inside save() runs?✅ Yes❌ No
Speed for bulk❌ Slow✅ Fast

🔥 5. Updating with F Expressions (Atomic Updates)

from django.db.models import F

NewUser.objects.filter(pk=1).update(credit_point=F('credit_point') + 10)

🛠 6. Update with Conditions (Smart Filtering)

NewUser.objects.filter(user_type=2, is_active=True).update(is_verified=True)

📋 7. Important Tips When Updating

  • Always use .save(update_fields=[...]) if you know what changed.
  • Use .update() if you want to bulk update many records.
  • Use F() expressions when updating values based on themselves (like counters).
  • Be careful: .update() skips signals and custom model logic.

🧠 8. Handling auto_now and Timestamps

from django.utils import timezone

NewUser.objects.filter(pk=1).update(modified_at=timezone.now())

🚀 9. Handling Race Conditions (Advanced)

from django.db import transaction

with transaction.atomic():
    user = NewUser.objects.select_for_update().get(pk=1)
    user.credit_point += 10
    user.save()

🎯 10. Best Practices for Updates

  • ✅ Always filter properly before updating.
  • ✅ Use .save(update_fields=...) if updating only some fields.
  • ✅ Use .update() when updating many records at once.
  • ✅ Be cautious: .update() skips signals and model logic.
  • ✅ Use F() expressions for safe, concurrent field changes.
  • ✅ Handle timestamps manually during .update().

📖 Final Example — Updating Cleanly

# Safe update of user email
user = NewUser.objects.get(pk=5)
user.email = 'updated_email@example.com'
user.save(update_fields=['email'])

# Bulk deactivate all sellers
NewUser.objects.filter(user_type=2).update(is_active=False)

# Increment credit points safely
NewUser.objects.filter(pk=5).update(credit_point=F('credit_point') + 50)

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