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How to delete a record in Django models?

I want to delete a particular record. Such as

delete from table_name where id = 1;

How can I do this in a django model?

Agreed with @Freedom_Ben, but for future readers that like the f* manual anyway, this is what you're looking for: docs.djangoproject.com/en/dev/topics/db/queries/…

W
Wolph

There are a couple of ways:

To delete it directly:

SomeModel.objects.filter(id=id).delete()

To delete it from an instance:

instance = SomeModel.objects.get(id=id)
instance.delete()

Note that the first one will not call the .delete() method of the object, so if you have 'cleanup' code in that method it will not be called. Generally not an issue, but worth keeping in mind.
@Matthew Schinckel: that is true. If you want to have a custom delete method than you should be using the pre_delete or post_delete signal instead.
I dont know what is the case after DJango 1.4, but this is actually fetching all the PKs and then delete by those PKs. So eg if you delete by an arbitrary field, this can be way slower then the SQL counterpart... :(
@VajkHermecz: that is true and the expected behaviour because of the delete signals. The Django signals system has to track all database changes because something could hook to it (like reversion does).
You can use the return value of delete() to check what you were deleting. It returns a tuple with the count of deleted objects and a dictionary with details about the deleted types, e.g. (1, {'yourapp.SomeModel': 1}).
M
Milad Khodabandehloo
MyModel.objects.get(pk=1).delete()

this will raise exception if the object with specified primary key doesn't exist because at first it tries to retrieve the specified object.

MyModel.objects.filter(pk=1).delete()

this wont raise exception if the object with specified primary key doesn't exist and it directly produces the query

DELETE FROM my_models where id=1

You have used pk, @Wolph used id. What is the difference?
With pk you are filtering using the table primary key. I think @Milad assumed that since @Wolf was using id he was searching on the primary key. Generally this could be wrong if you set a different field as primary key in your model
@Gathide You can see in django docs.djangoproject.com/en/3.2/topics/db/models/that id = models.BigAutoField(primary_key=True) Therefore, if you have not changed the defualt primary key of your model, both id or pk work because *pk refers to primary key.
C
ColeDrain

if you want to delete one instance then write the code

entry= Account.objects.get(id= 5)
entry.delete()

if you want to delete all instance then write the code

entries= Account.objects.all()
entries.delete()

A
Ahmed Adewale

If you want to delete one item

wishlist = Wishlist.objects.get(id = 20)
wishlist.delete()

If you want to delete all items in Wishlist for example

Wishlist.objects.all().delete()

K
KhairulBashar

Extending the top voted answer by wolph

Note that you should pass request as a parameter to your delete function in your views. An example would be like:

from django.shortcuts import redirect


def delete(request, id):
YourModelName.objects.filter(id=id).delete()

return redirect('url_name')

Which is 'the top voted comment'? It is better is you reference it, e.g. by its author, as it may not remain 'top' forever.
Z
Zoe stands with Ukraine

The delete() method is used to delete model instances from a database.This method immediately deletes the object. this method returns the number of object deleted.

Example:

For deleting one record:

data_to_be_deleted = Modelname.objects.get(fieldname = value)
data_to_be_deleted.delete()

As get method returns a single object from queryset only single record will be deleted.If value supplied doesn't exist this will throw an error.If there are multilpe records in table for same value then also it will throw an error so good practice is to use a single unique value while using get.

For deleting multiple record according to a condition:

For condition based deletion filter method is used on queryset and then delete is called.

data_to_be_deleted = Modelname.objects.filter(fieldname = value)
data_to_be_deleted.delete()

For deleting all records:

For deletion of all model instances/records from database table you need to call delete method on all

data_to_be_deleted = Modelname.objects.all()
data_to_be_deleted.delete()

Note: code can be written in single line as Modelname.objects.all().delete(), but for clear understanding, I have used multiple lines.


R
Radwan Abu-Odeh

It is as simple as calling the following.

SomeModel.objects.get(pk=1).delete()
# Or
SomeModel.objects.filter(pk=1).delete()

# SQL equivalent
# delete from table_name where id = 1;

In case you want to remove multiple records based on id, use the __in query lookup

SomeModel.objects.fitler(pk__in=[1,2,3,4,5,...]).delete()

# SQL equivalent
# delete from table_name where id in (1,2,4,5,...);

In case you want to delete all records, use .all() to retrieve all queries, then .delete().

SomeModel.objects.all().delete()

# SQL equivalent
# delete from table_name;

Z
Zoe stands with Ukraine

The way I do it:

instance = SomeModel.objects.get(id=1)

instance.delete()

For me it looks easy to understand, that's why I use this approach.


B
B S Mahesh Kumar

you can delete the objects directly from the admin panel or else there is also an option to delete specific or selected id from an interactive shell by typing in python3 manage.py shell (python3 in Linux). If you want the user to delete the objects through the browser (with provided visual interface) e.g. of an employee whose ID is 6 from the database, we can achieve this with the following code, emp = employee.objects.get(id=6).delete()

THIS WILL DELETE THE EMPLOYEE WITH THE ID is 6.

If you wish to delete the all of the employees exist in the DB instead of get(), specify all() as follows: employee.objects.all().delete()


S
Sunderam Dubey

You can also use get_object_or_404(), rather than directly using get() as while using get() we explicitly raise the error of 404.

But, while using get_object_or_404 it is automatically done.

get_object_or_404 According to 4.0 docs, Calls get() on a given model manager, but it raises Http404 instead of the model’s DoesNotExist exception.

Use it like:

For bulk deletion:

AnyModel.objects.filter(id=id).delete()

For deleting single instance, use get_object_or_404() instead of get() in the following way:

instance=get_object_or_404(anyModel,id=id)
instance.delete()

If, not found raises 404 automatically.