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How to get the ID of a just created record in Django?

I'm using Django 1.3 for one of my projects and I need to get the ID of a record just saved in the database.

I have something like the code below to save a record in the database:

n = MyData.objects.create(record_title=title, record_content=content)
n.save()

The ID of the record just saved auto-increments. Is there a way to get th开发者_JAVA百科at ID and use it somewhere else in my code?


Use n.id after the save.

See "Auto-incrementing primary keys".


It would be n.pk.

To quote "Model.pk":

Regardless of whether you define a primary key field yourself, or let Django supply one for you, each model will have a property called pk. It behaves like a normal attribute on the model, but is actually an alias for whichever attribute is the primary key field for the model. You can read and set this value, just as you would for any other attribute, and it will update the correct field in the model.


The ID will be automatically updated in your model, so immediately after your n.save() line you can read n.id and it will be populated.


Remove save() and get pk directly:

n = MyData.objects.create(record_title=title, record_content=content)
n.pk


If someone reading this question and after check the other answers still having problems accessing the id after the creation of the object. Be sure you don't define id as an Integer in your model. If you decide to declare it anyways, use Autofield but you don't need to, It is for free with models.Model

#No
class TestModel(models.Model):
    id = models.IntegerField(primary_key=True)
    something...


#Ok
class TestModel(models.Model):
    id = models.AutoField(primary_key=True)
    something...

#Ok
class TestModel(models.Model):
    something...

if you do define id as Integer, TestModel.objects.create( or with save() will return None.


I had a similar issue with accessing the id. In Django 3.0.5, this is how I accessed the id. Using your example and variable name, see below:

instance = n.save()
# return the id
instance[0].id 

The variable 'instance' above is a list. Accessing id in the methods described above returns an AttributeError ("object has no attribute 'id'") in Django 3.

This answer applies when using modelformset_factory. This is true when creating a Form class from a Django model as described in the Django docs

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