Aggregating save()s in Django?

EDITED: commit_on_success is deprecated and was removed in Django 1.8. Use transaction.atomic instead. See Fraser Harris’s answer.

Actually this is easier to do than you think. You can use transactions in Django. These batch database operations (specifically save, insert and delete) into one operation. I’ve found the easiest one to use is commit_on_success. Essentially you wrap your database save operations into a function and then use the commit_on_success decorator.

from django.db.transaction import commit_on_success

@commit_on_success
def lot_of_saves(queryset):
    for item in queryset:
        modify_item(item)
        item.save()

This will have a huge speed increase. You’ll also get the benefit of having roll-backs if any of the items fail. If you have millions of save operations then you may have to commit them in blocks using the commit_manually and transaction.commit() but I’ve rarely needed that.